WO2020258300A1

WO2020258300A1 - Identification apparatus and method

Info

Publication number: WO2020258300A1
Application number: PCT/CN2019/093870
Authority: WO
Inventors: 王玉栋; 陈华
Original assignee: 深圳市汇顶科技股份有限公司
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2020-12-30
Also published as: CN110463183A

Abstract

Provided are an identification apparatus and method. The apparatus comprises: a distance sensor used for measuring a first distance between an infrared sensor and an identification object; the infrared sensor, which is used for photographing a first image of the identification object at a preset exposure; and a processor used for determining the preset exposure according to the first distance, calculating the actual exposure of the infrared sensor according to the first image, and performing, when the actual exposure is in a preset range, identification processing on the identification object by using the first image. The present application can precisely determine a preset exposure of an infrared sensor. During 2D identification, there is no need to pre-photograph an image to determine whether the exposure is appropriate, which increases the identification speed of the apparatus; and furthermore, compared with the infrared sensor and a fill light, a distance sensor has lower energy consumption, thereby reducing the energy consumption of the apparatus. During 3D identification, by means of the apparatus, the exposure is adjusted according to the first distance, so that the apparatus is prevented from operating in a high-energy-consumption mode for a long time, reducing the energy consumption of the apparatus.

Description

Identification device and method

Technical field

The present invention relates to the technical field of face recognition, in particular to a recognition device and method.

Background technique

With the rise of 3D face recognition solutions, more and more products have begun to add 2D or 3D face recognition functions, such as smart phones, smart door locks, etc.

Whether it is 2D face recognition or 3D face recognition, infrared sensors are used, and infrared flood illuminators are required to fill light. As the distance and use environment change, the amount of fill light and the amount of exposure need to be adjusted. Figure 1 is a flow chart of an existing 2D face recognition solution. In the existing 2D face recognition solution, first, when the recognition device exposes some pixels, a frame of image is taken and the frame of image is exposed. Quantity analysis, if the exposure is appropriate, take a frame of image when all pixels are exposed, and perform 2D face recognition on the frame of image. However, the aforementioned 2D face recognition solution requires a pre-photograph of a face image to determine whether the exposure is appropriate, which results in longer recognition time and higher power consumption.

In addition, when using the recognition device for 3D face recognition, regardless of the distance between the recognition object and the recognition device, the exposure of the recognition device remains unchanged, that is, the drive current of the structured light projector in the recognition device and the exposure time of the infrared sensor are both Stay the same, resulting in greater power consumption.

Summary of the invention

The present application provides a recognition device and method, which aims to solve the technical problems that existing recognition devices require pre-photographed images to determine whether the exposure is appropriate when performing 2D face recognition, resulting in longer recognition time and higher power consumption, and The exposure amount of the existing recognition device remains unchanged when performing 3D face recognition, which causes a technical problem of high power.

In the first aspect, the present invention provides an identification device, including:

The distance sensor is used to measure the first distance between the infrared sensor and the recognition object;

Infrared sensor, used to shoot the first image of the recognized object under a preset exposure;

The processor is configured to determine the preset exposure level according to the first distance, calculate the actual exposure level of the infrared sensor according to the first image, and use the first image to perform recognition processing on the recognition object when the actual exposure level falls within the preset range.

Optionally, the processor is configured to generate a first instruction according to the first distance, and the first instruction is used to control the exposure time of the infrared sensor, so that the exposure level of the infrared sensor is the preset exposure level by controlling the exposure time.

Optionally, the device further includes: a fill light;

The fill light is connected to the infrared sensor; the infrared sensor generates a first drive signal according to the first instruction, and the first drive signal is used to control the intensity of the infrared light projected by the fill light, so as to control the exposure of the infrared sensor by controlling the intensity of the infrared light For the preset exposure.

Optionally, the device further includes: a fill light;

The fill light is connected to the infrared sensor; the first instruction is also used to make the infrared sensor generate a first drive signal, and the first drive signal is used to control the intensity of the infrared light projected by the fill light to control the exposure time and the intensity of the infrared light Control the exposure of the infrared sensor to the preset exposure.

Optionally, the device further includes: a structured light projector and a driving unit;

The structured light projector is connected to the driving unit, and the driving unit generates a second driving signal. The second driving signal is used to control the intensity of the structured light projected by the structured light projector. The exposure amount of the infrared sensor is controlled by controlling the intensity of the structured light. Set the exposure level.

The structured light projector is connected to the drive unit. The first instruction is also used to make the drive unit generate a second drive signal. The second drive signal is used to control the intensity of the structured light projected by the structured light projector to control the intensity and The exposure time controls the exposure of the infrared sensor to the preset exposure.

Optionally, the processor is connected to the drive unit;

The processor generates a first control signal according to the first instruction, and the drive unit generates a second drive signal according to the first control signal.

Optionally, the infrared sensor is connected to the drive unit;

The infrared sensor generates a second control signal according to the first instruction, and the driving unit generates a second driving signal according to the second control signal.

Optionally, the second driving signal includes: a synchronization signal and a configuration signal; the driving unit is respectively connected with the processor and the infrared sensor;

The processor generates a third control signal according to the first instruction, the infrared sensor generates a fourth control signal according to the first instruction, the drive unit generates a configuration signal according to the third control signal, and the drive unit generates a synchronization signal according to the fourth control signal.

Optionally, the first image is a 2D image or a 3D image.

In a second aspect, the present invention provides an identification method applied to an identification device, the identification device includes an infrared sensor and a distance sensor, and the method includes:

Acquiring the first distance between the identification object and the infrared sensor measured by the distance sensor;

Determining the preset exposure level of the infrared sensor according to the first distance;

Acquiring the first image taken by the infrared sensor under a preset exposure;

Calculate the actual exposure of the infrared sensor according to the first image;

If the actual exposure is within the preset range, the first image is used to identify the identification object.

Optionally, the identification device further includes: a fill light, which determines the preset exposure level of the infrared sensor according to the first distance, which specifically includes:

Determine the exposure time of the infrared sensor according to the first distance, and/or

The working current of the fill light is determined according to the first distance to determine the intensity of the infrared light projected by the fill light.

Optionally, the identification device further includes: a structured light projector, which determines the preset exposure of the infrared sensor according to the first distance, which specifically includes:

The working current of the structured light projector is determined according to the first distance to determine the intensity of the structured light projected by the structured light projector.

Optionally, the first image is a 2D image or a 3D image.

Optionally, if the actual exposure is outside the preset range, obtain the second distance between the identification object measured by the distance sensor and the infrared sensor;

If the first distance is the same as the second distance, the preset exposure level is adjusted according to the actual exposure level and the preset range.

Optionally, if the first distance is different from the second distance, the preset exposure amount is determined according to the second distance.

The present application provides an identification device and method. The identification device is provided with a distance sensor, and the first distance between the identification device and the identification object is measured by the distance sensor, so as to adjust the exposure of the identification device according to the first distance. The first image is taken under the preset exposure level, and if the actual exposure level of the first image is within the preset range, the first image is directly used to perform identification processing on the identification object. Compared with the prior art, the present application can accurately determine the preset exposure of the recognition device based on the first distance. When performing 2D recognition processing, there is no need to pre-photograph the image to determine whether the exposure is appropriate, and the recognition speed of the device is improved. For infrared sensors and fill lights, distance sensors consume less energy, thereby reducing the energy consumption of the identification device and increasing the standby time of the identification device. When performing 3D recognition processing, for recognizing objects at different positions, the recognition device can adjust its exposure according to the first distance, avoiding the recognition device from working in a high energy consumption mode for a long time, and reducing the energy consumption of the device.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description These are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

Fig. 1 is a schematic structural diagram of an identification device according to an exemplary embodiment of the present invention;

Fig. 2 is a schematic structural diagram of an identification device according to another exemplary embodiment of the present invention;

FIG. 3 is a layout diagram of the identification device based on the embodiment shown in FIG. 2;

Fig. 4 is a schematic structural diagram of an identification device according to another exemplary embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an identification device according to still another exemplary embodiment of the present invention;

Fig. 6 is a schematic flowchart of an identification method according to an exemplary embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of this application.

The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, without having to use To describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein, for example, can be implemented in a sequence other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations of them are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to the clearly listed Those steps or units may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or equipment.

Fig. 1 is a schematic structural diagram of an identification device according to an exemplary embodiment of the present invention. As shown in FIG. 1, this embodiment provides an identification device 100 that includes a distance sensor 101, an infrared sensor 102 and a processor 103. Among them, the relative position of the distance sensor and the infrared sensor is fixed.

When the recognition device 100 recognizes the recognition object, the distance sensor 101 measures the distance between itself and the recognition object. Since the relative position of the distance sensor and the infrared sensor is fixed, the infrared sensor 102 can be obtained according to the distance between the distance sensor and the recognition object. The first distance between and the recognized object. The processor 103 determines the preset exposure amount of the infrared sensor 102 according to the first distance. After determining the preset exposure level of the infrared sensor 102, the infrared sensor 102 shoots the first image of the recognized object under the preset exposure level, and the processor calculates the actual exposure level of the infrared sensor 103 according to the first image. If the actual exposure is within the preset range, the first image is used to perform recognition processing on the recognition object.

In the aforementioned identification device 100, the distance sensor 101 can measure the distance between the identification object and the identification device based on the TOF (Time of Flight) principle. The distance sensor 101 projects modulated light to the scene where the identification object is located. The modulated light is reflected after encountering the identification object. After the reflected light is collected by the distance sensor 101, it is convolved and sampled with the reference signal in the distance sensor 101 to obtain the reflected signal Then, the flight time of the modulated light can be obtained, and combined with the speed of light, the distance from the infrared sensor 102 to the identification object can be calculated.

In the above identification device 100, the distance sensor 101 can measure the distance between the identification object and the identification device based on the principle of ultrasonic waves. The distance sensor 101 emits ultrasonic waves to the scene where the recognition object is located, and starts timing when the ultrasonic waves are transmitted. The ultrasonic waves propagate in the air and reflect back immediately after encountering the recognition object. The distance sensor immediately stops timing when it receives the reflected waves. The propagation speed of ultrasonic waves in the air is 340m/s. According to the time recorded by the timer, the distance from the identification object to the infrared sensor 102 can be calculated.

In the above identification device 100, the distance sensor 101 may be based on the principle of infrared light sensing. The principle of infrared light sensing is the same as the TOF principle. The distance sensor 101 emits infrared modulated light to the scene where the identification object is located. After the object is reflected, the phase difference is determined according to the reflected infrared modulated signal and the reference infrared modulated light signal inside the distance sensor 101, and then the distance from the infrared sensor 102 to the identified object is calculated according to the phase difference.

In the above identification device 100, the distance sensor 101 may be other chips, modules, or solutions that realize distance detection. The type of the distance sensor 101 is not limited in this application.

In the above identification device, the gray values of some or all pixels of the first image are statistically analyzed to calculate and obtain the actual exposure of the first image. The above-mentioned preset range is determined according to the recognition accuracy of the user. And the recognition device can be used for 3D recognition processing and 2D recognition processing.

Compared with the prior art, the recognition device provided by this embodiment can accurately determine the preset exposure level of the infrared sensor 102 according to the first distance. When performing 2D recognition processing, there is no need to pre-photograph an image to determine whether the exposure level is appropriate. The recognition speed of the device, and compared with the infrared sensor and the fill light, the distance sensor consumes less energy, thereby reducing the energy consumption of the recognition device and increasing the standby time of the recognition device. When performing 3D recognition processing, for recognizing objects at different positions, the recognition device can adjust its exposure according to the first distance, avoiding the recognition device from working in a high energy consumption mode for a long time, and reducing the energy consumption of the device.

Fig. 2 is a schematic structural diagram of an identification device according to another exemplary embodiment of the present invention. As shown in FIG. 2, the identification device 200 provided by this embodiment includes: a distance sensor 201, a structured light projector 202, a driving unit 203, an infrared sensor 204, a fill light 205, an RGB sensor 206, a processor 207, and a memory 208 .

In the above identification device 200, the processor 207 is respectively connected to the distance sensor 201, the driving unit 203, the infrared sensor 204, the RGB sensor 206, and the memory 208, the driving unit 203 is connected to the structured light projector 202, and the infrared sensor 204 is connected to the supplementary light. The lamp 205 is connected.

When the aforementioned recognition device 200 is used for two-dimensional (2D) recognition processing, the distance sensor 201 measures the first distance from the infrared sensor 204 to the recognition object, and transmits the first distance to the processor 207, and the processor 207 Determine the preset exposure level of the infrared sensor 204 according to the first distance, the processor 207 generates a first instruction, the first instruction is used to control the exposure level of the infrared sensor 204 to the preset exposure level, and the recognition device shoots at the preset exposure level The first image, where the first image is a 2D image, and the 2D image is transmitted to the processor 207, so that the processor 207 performs 2D recognition processing on the recognition object according to the 2D image.

Wherein, when shooting a 2D image, determining the preset exposure level of the infrared sensor 204 specifically includes the following three specific implementation manners:

The first specific implementation is to control the exposure time of the infrared sensor 204 to make the exposure of the infrared sensor a preset exposure. The processor generates a first instruction according to the first distance. The first instruction is used to control the infrared sensor 204 to work at the first exposure time when the fill light 205 is working at the default operating current, that is, to determine when the fill light 205 is working at the default operating current. The shutter speed of the infrared sensor makes the exposure level of the infrared sensor 204 a preset exposure level, where the default operating current can be set according to user requirements. The driving circuit in the infrared sensor generates the first driving signal to drive the fill light to work. The fill light provides infrared light. By controlling the shutter speed of the infrared sensor to adjust the amount of light entering the infrared sensor, the infrared sensor shoots 2D images, which are calculated by the 2D image The actual exposure of the infrared sensor, when the actual exposure is within the preset range, the processor performs 2D recognition processing according to the 2D image.

The second specific implementation is to control the intensity of the infrared light projected by the fill light to make the exposure of the infrared sensor a preset exposure. The processor generates a first instruction according to the first distance. The first instruction is used to control the fill light 205 to work at the first working current under the default exposure time of the infrared sensor 204, that is, the infrared sensor confirms the fill light at the default shutter speed. Working current to control the intensity of infrared light projected by the fill light. Among them, the default shutter speed can be set according to user needs. The driving circuit in the infrared sensor generates a first driving signal to drive the fill light to work, and the fill light provides infrared light. By controlling the working current of the fill light to adjust the light input of the infrared sensor, the exposure of the infrared sensor 204 is preset Set the exposure level. The infrared sensor shoots a 2D image, and the actual exposure of the infrared sensor is calculated from the 2D image. When the actual exposure is within a preset range, the processor performs 2D recognition processing based on the 2D image.

The third specific implementation manner is to control the exposure time of the infrared sensor 204 and the intensity of the infrared light projected by the fill light so that the exposure level of the infrared sensor is the preset exposure level. The processor generates a first instruction according to the first distance. The first instruction is used to control the infrared sensor 204 to work at the first exposure time, and to control the fill light 205 to work at the second working current, passing the first exposure time and the second working current Jointly control the exposure of the infrared sensor. The driving circuit in the infrared sensor generates the first driving signal to drive the fill light to work. By controlling the working current of the fill light and the exposure time of the infrared sensor, the light input of the infrared sensor is adjusted so that the exposure of the infrared sensor 204 is preset Set the exposure level. The infrared sensor shoots a 2D image, and the actual exposure of the infrared sensor is calculated from the 2D image. When the actual exposure is within a preset range, the processor performs 2D recognition processing based on the 2D image.

More specifically, the controller allows the drive unit to provide structured light projectors with communication interfaces such as serial peripheral interface (Serial Peripheral Interface, SPI) or two-wire serial (Inter-Integrated Circuit, I2C) bus The second driving signal, where the second driving signal includes a configuration signal and a synchronization signal. The configuration signal is used to configure the drive current, frequency, duty cycle, etc. for the structured light projector. The synchronization signal is used to synchronize the exposure control of the structured light projector and the infrared sensor.

When the aforementioned recognition device 200 is used to perform three-dimensional (3Dimension, abbreviated: 3D) recognition processing, determining the exposure of the infrared sensor specifically includes the following three specific embodiments:

The first specific implementation manner is to control the exposure time of the infrared sensor 204 to make the exposure of the infrared sensor a preset exposure. The processor generates a first instruction according to the first distance. The first instruction is used to control the infrared sensor 204 and the structured light projector 202 to work at the first exposure time parameter when the infrared sensor 204 is operating at the default operating current, so that the exposure of the infrared sensor is the preset exposure the amount. Among them, the default operating current is set according to user requirements.

The second specific implementation is to control the intensity of the structured light projected by the structured light projector to make the exposure level of the infrared sensor a preset exposure level. The processor generates a first instruction according to the first distance, and the first instruction is used to control the structured light projector 202 to operate at the third operating current under the default exposure time of the infrared sensor 204 so that the exposure level of the infrared sensor is the preset exposure level. Among them, the default exposure time can be set according to user needs.

The third embodiment is to control the exposure time of the infrared sensor 204 and the intensity of the structured light projected by the structured light projector to make the exposure of the infrared sensor a preset exposure. The processor generates a first instruction according to the first distance. The first instruction is used to control the infrared sensor 204 to work at the first exposure time parameter, and to control the structured light projector 202 to work at the fourth operating current, passing the first exposure time and the fourth operating current. The working current makes the exposure of the infrared sensor the preset exposure.

Wherein, the processor generates a first control signal according to the first instruction, the first control signal is used to control the drive unit to generate a second drive signal, and the second drive signal is used to drive the structured light projector. The structured light is projected, and the processor controls the infrared sensor to work according to the first instruction. The infrared sensor shoots the first picture of the identified object under the structured light projection. The first picture is a 3D image, and the first picture is transmitted to the processor. So that the processor performs 3D processing on the recognized image according to the first picture.

The above-mentioned structured light projector can provide point structured light, line structured light, multi-line structured light, surface structured light and other forms of structured light. The above-mentioned fill light may be a flood illuminator, and the flood illuminator is used to provide uniform fill light.

When the aforementioned recognition device 200 is used to capture color images, the processor controls the operation of the RGB sensor to capture color images. Color images have two roles in the recognition process. The first function is to display the captured color image on the screen in real time, similar to a mirror, showing the location of the recognized object, so that the position of the recognized object can be adjusted in time to keep the recognized object within the recognition range. The second function is: color images can be used for color object recognition. For example: when the recognition object is a human face, the multi-spectral color data of the human face is combined with the facial image taken by the infrared sensor to realize more complex face recognition, such as living body detection and anti-counterfeiting.

The processor also calls information in the memory, such as calibration, template, feature, and system information stored in the memory, and generates various instructions to control the infrared sensor, RGB sensor, proximity sensor, and structured light projector.

FIG. 3 is a layout diagram of the identification device based on the embodiment shown in FIG. 2. As shown in FIG. 3, the fill light 205, the infrared sensor 204, the RGB sensor 206, the distance sensor 201, the structured light projector 202 and the driving unit 203 are assembled in an integrated module. The processor 207 and the memory 208 can be placed inside the module or on a separate motherboard. When the processor 207 and the memory 208 are placed on separate motherboards, the processor 207 is connected to the integrated module through a communication line. Wherein, the fill light 205, the RGB sensor 206, and the distance sensor 201 are located around the infrared sensor 204, and there is a certain distance between the infrared sensor 204 and the structured light projector 202. It should be noted that this embodiment does not limit the layout of each part of the identification device, and can be adjusted according to specific application scenarios.

If the identification object is a material that scatters light strongly, such as a human face. When light hits the surface of the recognition object, the distribution of its reflected light is close to ideal diffuse reflection. For a lens with a defined aperture value specification, the irradiance of light that can pass through the lens to the surface of the infrared sensor is inversely proportional to the square of the distance from the lens to the surface of the object to be identified. That is, the distance between the identification object and the infrared sensor is doubled, and the light input is reduced to 1/4 of the original. Therefore, the exposure of the infrared sensor can be determined according to the distance between the identification object and the identification device.

In the recognition device provided in this embodiment, the exposure of the infrared sensor can be accurately determined according to the distance, without pre-shooting the image of the recognition object, so that the recognition device consumes less energy and improves the recognition speed when performing 2D recognition. The recognition device does not need to work in a high energy consumption mode for a long time, which reduces energy consumption during 3D recognition.

Fig. 4 is a schematic structural diagram of an identification device according to another exemplary embodiment of the present invention. As shown in FIG. 4, the identification device 300 provided in this embodiment includes: a distance sensor 301, a structured light projector 302, a driving unit 303, an infrared sensor 304, a fill light 305, an RGB sensor 306, a processor 307, and a memory 308 .

In the above identification device 300, the processor 307 is electrically connected to the distance sensor 301, the infrared sensor 304, the RGB sensor 306, and the memory 308, the driving unit 303 is connected to the structured light projector 302, and the infrared sensor 304 is respectively connected to the fill light 305 Connected to the drive unit 303.

In this embodiment, when shooting 2D images and color images, the working principle of the recognition device is the same as the working principle of the recognition device in the embodiment shown in FIG. 2.

When shooting 3D images, the working principle of the recognition device differs from the working principle of the recognition device in the embodiment shown in FIG. 2 in that after the RGB sensor receives the first command, it generates a second control signal according to the first command signal, and passes the SPI Or a communication interface such as I2C sends the second control signal to the driving unit, and the driving unit is controlled to provide the second driving signal for the structured light projector. Under the control of the driving signal, the structured light projector projects structured light to the scene where the identification object is located, and the processor controls the infrared sensor to work. The infrared sensor obtains the picture projected by the structured light and transmits the picture to the processor for the processor to decode Calculate the 3D image.

In the identification device provided in this embodiment, the infrared sensor controls the driving unit to provide a driving signal for the structured light projector, which can more accurately realize the synchronization of the structured light projector and the infrared sensor, so as to improve the accuracy of identification.

Fig. 5 is a schematic structural diagram of an identification device according to another exemplary embodiment of the present invention. As shown in FIG. 5, the identification device 400 provided by this embodiment includes: a distance sensor 401, a structured light projector 402, a driving unit 403, an infrared sensor 404, a fill light 405, an RGB sensor 406, a processor 407, and a memory 408 .

In the above identification device 400, the processor 407 is electrically connected to the distance sensor 401, the driving unit 403, the infrared sensor 404, the RGB sensor 406 and the memory 408, the driving unit 403 is connected to the structured light projector 402, and the infrared sensor 404 is respectively connected to The fill light 405 is connected to the driving unit 403.

When shooting 3D images, the working principle of the recognition device differs from that in the embodiment shown in FIG. 2 in that the processor generates a third control signal according to the first instruction, and transmits the third control signal through a communication interface such as SPI or I2C. The control signal is sent to the drive unit to control the drive unit to provide configuration signals to the structured light projector. The infrared sensor generates a fourth control signal according to the first instruction, and sends the fourth control signal to the drive unit through a communication interface such as SPI or I2C to control The driving unit provides a synchronization signal to the structured light projector, so that the structured light projector provides structured light under the common control of the configuration signal and the synchronization signal. At the same time, the processor controls the infrared sensor to work. The infrared sensor acquires the picture projected by the structured light and transmits the picture to the processor so that the processor can calculate the 3D image.

In the identification device provided in this embodiment, the infrared sensor only controls the driving unit to provide synchronization signals for the structured light projector, and the function of generating configuration signals is transferred to the processor to control the generation of the driving unit, making the infrared sensor simple in structure and improving structured light projection Synchronization of the sensor and infrared sensor.

Fig. 6 is a schematic flowchart of an identification method according to an exemplary embodiment of the present invention. As shown in Figure 6, the identification method provided in this embodiment includes the following steps:

S501: Acquire a first distance between the recognition object and the recognition device.

More specifically, in this embodiment, a distance sensor is used to obtain the first distance between the recognition object and the recognition device. The distance sensor may obtain the first distance based on the TOF principle, the ultrasonic principle, the infrared light sensing principle, or other methods.

S502: Determine a preset exposure amount of the infrared sensor according to the first distance.

More specifically, since the light intensity collected by the identification device is inversely proportional to the square of the distance between the identification device and the identification object, the light intensity collected by the infrared sensor can be obtained according to the first distance. The light intensity collected by the identification device is then used to determine the preset exposure of the identification device.

In this embodiment, the identification device includes an infrared sensor, a structured light projector, and a fill light. After obtaining the first distance between the identification device and the identification object, the following three specific implementation methods can be adopted to determine the preset exposure of the infrared sensor. The first specific implementation is to determine the exposure time of the infrared sensor according to the first distance, so as to determine the preset exposure of the infrared sensor. The second specific implementation manner is: determining the operating current of the fill light according to the first distance, or determining the operating current of the structured light projector according to the first distance, so as to determine the preset exposure of the infrared sensor. The third specific implementation is to determine the operating current of the fill light and the exposure time of the infrared sensor according to the first distance to determine the preset exposure of the infrared sensor, or determine the operation of the structured light projector according to the first distance The current and the exposure time of the infrared sensor are used to determine the preset exposure of the infrared sensor.

S503: Acquire a first image shot under a preset exposure amount.

S504: Calculate the actual exposure of the infrared sensor according to the first image.

More specifically, the recognition device shoots a first image of the recognition object under a preset exposure, performs statistics on the gray values of some or all pixels of the first image, and obtains the actual exposure of the infrared sensor according to the statistical result.

S505: Judge whether the actual exposure is within the preset range, if the judgement result is yes, then go to S505, otherwise, go to S507.

S506: Recognize the recognition object according to the first image.

More specifically, if the first image is a 2D image, the first image can be used for 2D recognition processing, and if the first image is a 3D image, the first image can be used for 3D recognition processing.

S507. Acquire a second distance between the recognition object and the recognition device.

More specifically, in order to determine whether the position of the recognition object and the recognition device has changed, the distance between the face and the recognition device is acquired again as the second distance.

S508: Determine whether the second distance is the same as the first distance, and if the judgment result is yes, then go to S509, otherwise go to S510.

S509: Adjust the preset exposure level according to the actual exposure level and the preset range.

When the position of the face and the recognition device does not change, obtain the difference between the actual exposure and the preset range. For example, if the preset range is between 900 and 1000 and the actual exposure is 800, then the actual exposure and the preset Set the difference in the range to be 100-200, and then adjust the exposure of the identification device according to the difference, so that the exposure of the identification device is between 900-1000.

S510: Determine the preset exposure amount according to the second distance.

When the position of the recognition object and the recognition device changes, the preset exposure level of the infrared sensor is determined according to the second distance.

In the identification method provided in this embodiment, the exposure of the infrared sensor can be accurately determined according to the distance between the identification object and the identification device. If the actual exposure is within the preset exposure range, the first image is used for identification directly without Pre-shooting images reduces energy consumption and improves recognition speed when the recognition device performs 2D processing. The recognition device does not need to work in a high energy consumption mode for a long time, which reduces energy consumption during 3D recognition.

A person of ordinary skill in the art can understand that all or part of the steps in the foregoing method embodiments can be implemented by a program instructing relevant hardware. The aforementioned program can be stored in a computer readable storage medium. When the program is executed, it executes the steps including the foregoing method embodiments; and the foregoing storage medium includes: ROM, RAM, magnetic disk, or optical disk and other media that can store program codes.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand: It is still possible to modify the technical solutions described in the foregoing embodiments, or equivalently replace some or all of the technical features; these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention range.

Claims

An identification device, characterized by comprising:

The distance sensor is used to measure the first distance between the infrared sensor and the recognition object;

The infrared sensor is used to shoot the first image of the recognition object under a preset exposure;

The processor is configured to determine the preset exposure level according to the first distance, calculate the actual exposure level of the infrared sensor according to the first image, and use when the actual exposure level falls within a preset range The first image performs recognition processing on the recognition object.
The device according to claim 1, wherein the processor is configured to generate a first instruction according to the first distance, and the first instruction is used to control the exposure time of the infrared sensor to control the The exposure time is such that the exposure level of the infrared sensor is the preset exposure level.
The device according to claim 1, wherein the device further comprises: a fill light;

The fill light is connected to the infrared sensor; the processor is configured to generate a first instruction according to the first distance, the infrared sensor generates a first drive signal according to the first instruction, and the first drive signal It is used to control the intensity of the infrared light projected by the fill light, and control the exposure of the infrared sensor by controlling the intensity of the infrared light as the preset exposure.
The device according to claim 2, wherein the device further comprises: a fill light;

The fill light is connected to the infrared sensor; the first instruction is also used to make the infrared sensor generate a first drive signal, and the first drive signal is used to control the infrared light projected by the fill light Intensity, the exposure amount of the infrared sensor controlled by controlling the exposure time and the intensity of the infrared light is the preset exposure amount.
The device according to claim 1, wherein the device further comprises: a structured light projector and a driving unit;

The structured light projector is connected to the drive unit, and the drive unit generates a second drive signal. The second drive signal is used to control the intensity of the structured light projected by the structured light projector to control the The intensity of structured light controls the exposure of the infrared sensor to the preset exposure.
3. The device of claim 2, wherein the device further comprises: a structured light projector and a driving unit;

The structured light projector is connected to the driving unit, and the first instruction is also used to make the driving unit generate a second driving signal, and the second driving signal is used to control the structure of the structured light projector to project The intensity of the light is the preset exposure level by controlling the intensity of the structured light and the exposure time to control the exposure level of the infrared sensor.
The device according to claim 5 or 6, wherein the processor is connected to the drive unit;

The processor generates a first control signal according to the first instruction, and the driving unit generates a second drive signal according to the first control signal.
The device according to claim 5 or 6, wherein the infrared sensor is connected to the driving unit;

The infrared sensor generates a second control signal according to the first instruction, and the driving unit generates a second driving signal according to the second control signal.
The device according to claim 5 or 6, wherein the second driving signal comprises: a synchronization signal and a configuration signal; the driving unit is connected to the processor and the infrared sensor respectively;

The processor generates a third control signal according to the first instruction, the infrared sensor generates a fourth control signal according to the first instruction, the drive unit generates the configuration signal according to the third control signal, and the drive The unit generates the synchronization signal according to the fourth control signal.
The device according to claim 1 or 2, wherein the first image is a 2D image or a 3D image.
An identification method, characterized in that it is applied to the identification device, the identification device includes an infrared sensor and a distance sensor, and the method includes:

Acquiring the first distance between the identification object measured by the distance sensor and the infrared sensor;

Determining the preset exposure amount of the infrared sensor according to the first distance;

Acquiring a first image taken by the infrared sensor under the preset exposure amount;

Calculating the actual exposure of the infrared sensor according to the first image;

If the actual exposure is within a preset range, the first image is used to identify the identification object.
The method according to claim 11, wherein the identification device further comprises: a fill light, and the determining the preset exposure amount of the infrared sensor according to the first distance specifically includes:

Determine the exposure time of the infrared sensor according to the first distance, and/or

The operating current of the supplement light lamp is determined according to the first distance to determine the intensity of the infrared light projected by the supplement light lamp.
The method according to claim 11, wherein the identification device further comprises: a structured light projector, and the determining the preset exposure amount of the infrared sensor according to the first distance specifically includes:

Determine the exposure time of the infrared sensor according to the first distance, and/or

The working current of the structured light projector is determined according to the first distance to determine the intensity of the structured light projected by the structured light projector.
The method according to claim 11, wherein the first image is a 2D image or a 3D image.
The method according to any one of claims 11 to 14, characterized in that:

If the actual exposure is outside the preset range, acquiring the second distance between the identification object and the infrared sensor measured by the distance sensor;

If the first distance is the same as the second distance, the preset exposure level is adjusted according to the actual exposure level and the preset range.
The method according to claim 15, characterized in that:

If the first distance is different from the second distance, the preset exposure amount is determined according to the second distance.