What are the integrated face access control hardware?

The current face-access control product is an integrated face-access control product with a screen. Due to the large number of manufacturers, various product functional components, and large differences in product performance indicators, it is often difficult for users to select face access control products. Objective indicators for device evaluation of face access control. This chapter compares the main product modules of the integrated face access control with the mainstream technical solutions, and provides technical specifications for the product manufacturers to design and develop face access control products and users to select face access control products.

The following describes an integrated access control product directly referred to as an access control product.

Integrated access control product composition

The integrated face access control product usually consists of a camera module, a human body sensing module, a fill light module, a proximity card or a keyboard, a main control board, a display screen, and a linkage output module. Some products replace the keyboard with a touch screen, or directly save the sensor card module, which is related to product design positioning.

Camera imaging module

The camera imaging module is a key component of the integrated face access control product, which is related to the acquisition capability and application range of face recognition imaging. The main technical parameters affecting the camera imaging module are key indicators such as interface type, sensitization range and number of lenses.

Basic Principles A typical camera module consists of a lens, sensor, ISP module, and video encoding module. Depending on the interface type, the ISP or video encoding module may also be integrated on the main control board.

Lens. The main parameters are focal length, aperture and depth of field. With regard to focal length, aperture and depth of field, more optical content is involved and will not be expanded here.

Sensor sensor. It determines the low illumination and wide dynamic imaging capability of the lens, and determines whether the access control device is suitable for outdoor applications and indoor applications.

Digital signal processing ISP. A variety of functions such as image white balance, distortion correction, and focus control.

Image coding. It is related to the type of camera module. USB and MIPI cameras usually do not perform video compression coding. The webcam involves video compression coding.

Camera module imaging device face access is generally a highly integrated product, camera modules often come from computer cameras, cameras or security surveillance cameras.

According to the camera's imaging chip source, it can be divided into the following types:

The first category: indoor imaging camera module based on computer camera

Desktop USB cameras for laptops and desktops are usually used in indoor applications such as desktops and foregrounds. The distance between the person being photographed and the device is usually within 1 meter. The indoor light is bright and stable without large changes. The indoor imaging camera module with the computer camera as the main body has been widely used in face access control.

The typical indicators of the desktop imaging camera module are: face detection distance: less than 1 meter; face resolution: mainly D1, 720P or 1080P; wide dynamic light adaptability: require light to be even on the face , does not have the ability to adapt to wide light dynamics. Low illumination imaging capability: The suitable imaging illumination is 100-3000 Lux, and it does not have low illumination imaging capability. Scope of application: face detection and recognition in indoor access control or in good environment.

The second category: the camera-based wide dynamic imaging module, the imaging capabilities of a large number of smart camera modules have been greatly improved, the mainstream camera has a qualitative change in the imaging quality relative to the desktop USB camera. These cameras are usually based on MIPI interface cameras, and a few still exist as USB interfaces. The typical indicators with a certain degree of wide dynamic module based on the camera module are: Face detection distance: 0.5m-2m; Face definition: 720P or 1080P; Wide dynamic light adaptability : Wide dynamic imaging capability of 60db-80db. Low illumination imaging capability: capable of imaging low light, suitable imaging illumination of 30-3000 Lux, primary low illumination imaging. Scope of application: indoor or floor, unit door imaging with light-filling environment.

The third category: low-illuminance wide dynamic imaging module based on security surveillance camera chip security camera is usually outdoor, and must adapt to a variety of scenes such as strong light, low light at night, security camera professional-grade imaging chip Has a good low illumination wide dynamic imaging capabilities. Typical indicators of this type of module are: Face detection distance: 0.5m-5m; Face resolution: 720P or 1080P; Wide dynamic light adaptability: Wide dynamic imaging capability of 80db-100db. Low illumination imaging capability: It can image low or low light, and the suitable imaging illumination is 0.1-5000 Lux. Scope of application: outdoor face recognition of parks and communities, face recognition applications for outdoor entrances and exits.

The interface type of the camera interface type camera module has a great relationship with the size and application range of the camera. There are mainly the following interface types A.USB common computer camera usually most USB cameras. The USB camera is currently the most widely used camera module, featuring high market share and good compatibility.

Universal Serial Bus (USB) is a serial bus standard for connecting computer systems and external devices. It is also a technical specification for input and output interfaces, and is widely used in personal computers and mobile devices. Information and communication products, and extended to photographic equipment, digital TV (set-top boxes), game consoles and other related fields. It is USB 3.1, the transmission speed is 10Gbit/s, the three-stage voltage is 5V/12V/20V, and the maximum power supply is 100W. The new Type C plug-in is no longer positive and negative. USB is a commonly used pc interface. It has only 4 wires, two power supplies and two signals, so the signal is serially transmitted, and the usb interface is also called serial port.