A depth measurement system and method

Abstract

The present application provides a depth measurement system and method, wherein the acquisition module first generates an event signal by acquiring the reflected light signal reflected by the target object through an event pixel array; the processor generates an event image according to the event signal, and when the target object in the event image is identified as a valid measurement object, the processor sends a depth pixel activation instruction to the acquisition module; the acquisition module then responds to the depth pixel activation instruction and acquires the reflected light signal through the depth pixel array to generate an electrical signal; the processor finally calculates the depth value of the target object based on the electrical signal. Through the implementation of the scheme of the present application, whether the depth measurement conditions are met is first detected through event pixels, and the depth measurement is turned on only when the conditions are met, which can reduce the power consumption of the transmitting module and the acquisition module, and at the same time reduce the memory occupied by redundant data.

Description

Technical Field

[0001] The present application relates to the field of machine vision technology, and in particular to a depth measurement system and method. Background Art

[0002] The depth measurement system can be used to obtain the depth image of the object, and further perform 3D modeling, skeleton extraction, face recognition, etc. It has a wide range of applications in the fields of 3D measurement and human-computer interaction. The current depth measurement technologies mainly include TOF ranging technology and structured light ranging technology.

[0003] TOF ranging technology is a technology that achieves accurate ranging by measuring the round-trip flight time of light pulses between the transmitting / receiving device and the target object. It is divided into direct ranging technology and indirect ranging technology. Among them, the indirect ranging technology measures the phase delay of the reflected light signal relative to the transmitted light signal, and then calculates the flight time based on the phase delay. According to the different modulation and demodulation types, it can be divided into continuous wave (CW) modulation and demodulation methods and pulse modulation (PW) modulation and demodulation methods.

[0004] The structured light ranging technology emits a structured light beam to a space object, then collects the structured light pattern formed by the modulated and reflected structured light beam, and finally uses triangulation to perform depth calculation to obtain the depth data of the object.

[0005] However, both of these distance measurement technologies require the depth measurement system to be in operation all the time, and the power consumption of the transmitter and receiver is relatively high, and the memory requirements are also high. Summary of the invention

[0006] The embodiments of the present application provide a depth measurement system and method, which can at least solve the problem that the distance measurement technology provided in the related art requires the depth measurement system to always remain in a working state, resulting in high power consumption and high memory usage.

[0007] A first aspect of an embodiment of the present application provides a depth measurement system, including: a transmitting module, a collecting module and a processor;

[0008] The emission module is used to project emission light toward the target object;

[0009] The acquisition module is used to acquire the reflected light signal reflected by the target object through the event pixel array in an initial state, and generate an event signal according to the reflected light signal, and in response to the depth pixel activation instruction sent by the processor, acquire the reflected light signal through the depth pixel array, and generate an electrical signal according to the reflected light signal;

[0010] The processor is used to generate an event image according to the event signal, and when the target object in the event image is identified as a valid measurement object, send the depth pixel activation instruction to the acquisition module, and then calculate the depth value of the target object based on the electrical signal.

[0011] A second aspect of an embodiment of the present application provides a depth measurement method, which is applied to a depth measurement system including a transmitting module, a collecting module and a processor, including:

[0012] The emission module projects emission light toward the target object;

[0013] The acquisition module acquires the reflected light signal reflected by the target object through the event pixel array in the initial state, and generates an event signal according to the reflected light signal;

[0014] The processor generates an event image according to the event signal, and sends a depth pixel activation instruction to the acquisition module when identifying that the target object in the event image is a valid measurement object;

[0015] The acquisition module responds to the depth pixel activation instruction sent by the processor, acquires the reflected light signal through the depth pixel array, and generates an electrical signal according to the reflected light signal;

[0016] The processor calculates a depth value of the target object based on the electrical signal.

[0017] As can be seen from the above, according to the depth measurement system and method provided by the present application, the acquisition module first generates an event signal by collecting the reflected light signal reflected by the target object through the event pixel array; the processor generates an event image according to the event signal, and when the target object in the event image is identified as a valid measurement object, the processor sends a depth pixel activation instruction to the acquisition module; the acquisition module then responds to the depth pixel activation instruction and collects the reflected light signal through the depth pixel array to generate an electrical signal; the processor finally calculates the depth value of the target object based on the electrical signal. Through the implementation of the present application, whether the depth measurement conditions are met is first detected through event pixels, and the depth measurement is turned on only when the conditions are met, which can reduce the power consumption of the transmitting module and the acquisition module, and at the same time reduce the memory occupied by redundant data. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the structure of a depth measurement system provided in the first embodiment of the present application;

[0019] Figure 2 A schematic diagram of a pixel array composed of a plurality of pixels provided in the first embodiment of the present application;

[0020] Figure 3A schematic diagram of a basic flow chart of a depth measurement method provided in the second embodiment of the present application;

[0021] Figure 4 A schematic diagram of the structure of a terminal device provided in the third embodiment of the present application. DETAILED DESCRIPTION

[0022] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0023] In the description of the embodiments of the present application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0025] In the embodiments of the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0026] The above description is only a preferred embodiment of the present application and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

[0027] In order to solve the problem that the distance measurement technology provided in the related art requires the depth measurement system to keep working all the time, resulting in high power consumption and high memory usage, the first embodiment of the present application provides a depth measurement system, such as Figure 1 FIG. 1 is a schematic diagram of the structure of a depth measurement system provided in this embodiment. The depth measurement system 10 mainly includes: a transmitting module 11, a collection module 12, and a processor 13 connected to the transmitting module 11 and the collection module 12 respectively; wherein,

[0028] The emission module 11 is used to project emission light 30 toward the target object 20;

[0029] The acquisition module 12 is used to acquire the reflected light signal 40 reflected by the target object 20 through the event pixel array in the initial state, and generate an event signal according to the reflected light signal 40, and to acquire the reflected light signal 40 through the depth pixel array in response to the depth pixel activation instruction sent by the processor 13, and generate an electrical signal according to the reflected light signal 40; wherein the acquisition module 12 includes an image sensor 121 composed of a plurality of sub-pixel arrays;

[0030] The processor 13 is used to generate an event image according to the event signal, and when the target object 20 in the event image is identified as a valid measurement object, it sends a depth pixel activation instruction to the acquisition module 12, and then calculates the depth value of the target object 20 based on the electrical signal.

[0031] In practical applications, the depth measurement system 10 of this embodiment may further include a distance sensor 14. The processor 13 is further configured to send a distance measurement instruction to the distance sensor 14. The distance sensor 14 is configured to detect a distance value of the target object according to the distance measurement instruction.

[0032] In some implementations of this embodiment, the emission module 11 includes a light source and a light source driver (not shown). Among them, the light source can be implemented by a light source of a light emitting diode (LED), an edge emitting laser (EEL), a vertical cavity surface emitting laser (VCSEL), etc., or it can be implemented by a light source array composed of multiple light sources. In this embodiment, a VCSEL array is preferably used as a light source. VCSEL has the characteristics of small size, small light source emission angle, good stability, etc. In practical applications, multiple VCSEL light sources can be arranged on a semiconductor substrate. The VCSEL light source array chip thus formed is not only small in size and low in power consumption, but also more conducive to generating a spot pattern light beam. It should be understood that the arrangement of multiple VCSEL light source arrays can be reasonably set according to demand, such as regular arrangement or irregular arrangement. Different arrangement methods will output spot patterns in different areas accordingly, such as whether the arrangement of spots in the spot pattern is regular or irregular, whether the arrangement density of the spots is dense, etc. This embodiment preferably adopts an irregular arrangement method, which can increase the arrangement density of the spots. In addition, the light beam emitted by the light source of this embodiment can be visible light, infrared light, ultraviolet light, etc., which is not particularly limited in this embodiment.

[0033] In some implementations of this embodiment, the transmitting module 11 further includes an optical element, which is used to receive the light beam emitted by the light source and expand the received light beam to expand the field of view of the measuring device. The optical element can be one or a combination of lenses, diffractive optical elements (DOE), microlens arrays, and liquid crystals.

[0034] In some implementations of this embodiment, the acquisition module 12 includes an image sensor 121 composed of a plurality of sub-pixel arrays, a lens unit, and may also include a filter (not shown). The lens unit receives and images at least part of the reflected light reflected by the target object 20 on the image sensor 121; the filter is a narrow-band filter that matches the wavelength of the light source of the emission module to suppress the background light noise of the remaining bands. The image sensor may be a graphic sensor composed of a charge coupled device (CCD), a complementary metal oxide semiconductor (CMOS), an avalanche diode (AD), a single photon avalanche diode (SPAD), etc. The size of the sensor array represents the resolution of the camera, such as 320x240, etc. Generally, the image sensor 121 is also connected to a readout circuit (not shown) composed of one or more of a signal amplifier, a time-to-digital converter (TDC), an analog-to-digital converter (ADC), etc. It should be noted that the acquisition module of this embodiment may also include a fill light, which emits a light beam to fill light on the target object, so that the light reflected by the target object meets the light signal acquisition requirements.

[0035] In some implementations of this embodiment, the processor 13 can be an independent dedicated circuit, such as a dedicated SOC chip, FPGA chip, ASIC chip, etc. composed of a CPU, memory, bus, etc., or it can include a general-purpose processing circuit. For example, when the device is integrated into a smart terminal such as a mobile phone, a television, a computer, etc., the processing circuit in the smart terminal can serve as at least a part of the processor 13.

[0036] It should be noted that, in this embodiment, the event signal is first captured by the event pixel array (i.e., EVS pixel array) in the acquisition module 12 to capture the light intensity change of the scene, and the event pixel will only output the event image when there is an event, and its data volume is very small. Then, after the event image is generated based on the event signal, image recognition is performed to identify whether the target object in the current scene is a specific object (i.e., an effective measurement object, such as a person or a vehicle, etc.) that needs to be measured in depth. If so, the depth pixel array (e.g., APS pixel array or TOF pixel array) is selected to activate to trigger the depth measurement. It should be noted that APS pixel is a key technology of CMOS imager, and TOF (Time-of-Flight) pixel is a time-of-flight pixel. For example, in the field of face recognition, if it has been working in the traditional depth measurement mode, the power consumption of the emission module 11 and the acquisition module 12 is relatively large, but in this embodiment, the EVS (Event-based Camera) pixel is first used to detect whether an event is generated, and to determine whether it is a face, and then decide whether to turn on the depth measurement system. In this way, the data volume of the memory can be reduced while reducing the power consumption of the emission module 11 and the acquisition module 12.

[0037] In some implementations of this embodiment, the acquisition module 12 includes a switchable pixel array, which is an event pixel array in an initial state. Correspondingly, when the acquisition module 12 executes the function of collecting reflected light signals through the depth pixel array in response to the depth pixel activation instruction sent by the processor 13, it is specifically used to: control the event pixel array to switch to the depth pixel array in response to the depth pixel activation instruction sent by the processor 13; collect reflected light signals through the depth pixel array.

[0038] Specifically, in the present embodiment, the image sensor of the acquisition module 12 is configured with a switchable pixel array, which is an EVS pixel array in an initial state. When an event signal is acquired through the EVS pixel array and it is determined that the event image includes a valid measurement object, the original EVS pixel array is switched to a depth pixel array (for example, an APS pixel array) according to a depth pixel activation instruction sent by the processor 13. By configuring the pixel array to a switchable mode, it can be ensured that as many pixels as possible perceive reflected light in different signal acquisition stages, thereby improving image resolution.

[0039] In some implementations of this embodiment, the depth measurement system 10 further includes a distance sensor 14, and the acquisition module 12 includes a plurality of depth pixel arrays with different measurement accuracies; the distance sensor 14 is used to detect the distance value of the target object. Correspondingly, when the processor 13 executes the function of sending a depth pixel activation instruction to the acquisition module 12, it is specifically used to: compare the distance value with a preset depth threshold, and select a depth pixel array with a corresponding measurement accuracy according to the comparison result; and send a depth pixel activation instruction corresponding to the selected depth pixel array.

[0040] Specifically, the acquisition module 12 of the present embodiment supports a variety of different depth measurement modes, which can be implemented based on a variety of different depth pixel arrays, such as APS pixel arrays and TOF pixel arrays. In the present embodiment, the distance value of the target object is first obtained by the distance sensor 14, and then the processor 13 compares the distance value with the preset threshold value, and then adaptively activates the corresponding depth pixel array to perform depth measurement according to the comparison result to obtain the depth value. It should be understood that the distance value measured by the distance sensor 14 only includes the distance value of a single point or a few points, while the depth value measured by the depth pixel array includes the distance values ​​of more points, such as the distance value of the acquisition point within the entire viewing angle. In addition, it should be noted that the present embodiment uses the distance value initially measured by the distance sensor 14 as a reference to select a depth pixel array that ensures measurement accuracy, which is more accurate than blindly selecting a specific depth pixel array or selecting a specific depth pixel array by default for depth measurement.

[0041] In some other implementations of the present embodiment, when the processor 13 executes the function of sending a depth pixel activation instruction to the acquisition module 12 and then calculating the depth value of the target object based on the electrical signal, it is specifically used to: send a first depth pixel activation instruction to the acquisition module 12; wherein the first depth pixel activation instruction is used to trigger the acquisition module 12 to obtain a first electrical signal through a first depth pixel array; calculate a first depth value based on the first electrical signal, and compare the first depth value with a preset depth threshold; when the first depth threshold exceeds the range specified by the depth threshold, send a second depth pixel activation instruction to the acquisition module 12, wherein the second depth pixel activation instruction is used to trigger the acquisition module 12 to obtain a second electrical signal through a second depth pixel array; calculate a second depth value based on the second electrical signal, and use the second depth value as the depth value of the target object 20.

[0042] Specifically, similar to the previous embodiment, the acquisition module 12 supports a variety of different depth measurement modes, and in this embodiment, in the initial state, one of the depth pixel arrays can be defaulted to perform preliminary distance measurement, and then the measured depth value is compared with the preset threshold. When the measured depth value exceeds the range defined by the threshold, it means that the depth pixel array used at that time is not suitable, and other depth pixel arrays are activated to perform depth measurement. It should be noted that the first depth pixel array of this embodiment can preferably be an APS pixel array, and the second depth pixel array can be a TOF pixel array, and the measurement accuracy of the first depth value is lower than the accuracy of the second depth value.

[0043] Furthermore, in some implementations of the present embodiment, the acquisition module 12 includes a switchable pixel array and a second depth pixel array. The switchable array is an event pixel array in an initial state, and the first depth pixel activation instruction is specifically used to: trigger the acquisition module 12 to switch the event pixel array to the first depth pixel array, and obtain the first electrical signal through the first depth pixel array.

[0044] like Figure 2 The figure shows a schematic diagram of a pixel array provided in the present embodiment. In the present embodiment, the image sensor may be provided with two sub-pixel arrays, namely, a first sub-pixel array 201 and a second sub-pixel array 202, wherein the first sub-pixel array 201 is a switchable pixel array, which is an EVS pixel array by default. When an APS pixel activation instruction is received, it supports switching to an APS pixel array, thereby improving the image resolution, and the second pixel array 202 is directly set to a separate TOF pixel array. Of course, in other embodiments, the image sensor may also be set to three types of independent sub-pixel arrays, that is, different areas of the image sensor are respectively set to an EVS pixel array, an APS pixel array, and a TOF pixel array.

[0045] In some implementations of the present embodiment, the transmitting module 11 is also used to: project transmitted light to a calibration object at different measuring distances within a preset measurement range; the acquisition module 12 is also used to respectively acquire reflected light signals reflected back by the calibration object through multiple depth pixel arrays with different measurement accuracy, and generate a calibration electrical signal based on the reflected light signal; the processor 13 is also used to respectively calculate the calibration depth values ​​based on the calibration electrical signals corresponding to the depth pixel arrays with different measurement accuracy, and determine the corresponding measurement distance when the corresponding calibration depth values ​​of different depth pixel arrays are equal as the depth threshold.

[0046] Specifically, the present embodiment will further explain the setting of the depth threshold: the depth threshold can be obtained by pre-calibration, for example, the device 10 is calibrated every 10 cm within the distance measurement range from the minimum measurement distance to the maximum measurement distance, and the emission module 11 emits a light beam to the calibration object; the acquisition module 12 activates the APS pixel and the TOF pixel in turn to receive the light beam reflected by the calibration object and converts it into an electrical signal; the processor 13 calculates based on the electrical signal to obtain the distance of the calibration object when the APS pixel is activated and the distance of the calibration object when the TOF pixel is activated. It can be understood that at the position of a certain calibration plate, the distances of the calibration object measured by the processor 13 when activating the APS pixel and activating the TOF pixel are equal, and the measured distance of the calibration object at this time is the depth threshold. Of course, the above threshold setting method of the present embodiment is only a preferred implementation and does not constitute a sole limitation.

[0047] In some implementations of this embodiment, the emission module 11 includes a spot projector and liquid crystal; wherein the spot projector is used to provide output light; the liquid crystal is used to trigger a corresponding physical state according to a resolution requirement indicator, and based on the output light, project the emission light to the target object 20 accordingly in the physical state; wherein the physical state includes a diffuse state and a transparent state.

[0048] Specifically, in the present embodiment, the spot projector is configured to provide output light in a spot pattern having a plurality of spots, and the liquid crystal is configured to be controllable to switch state to receive the spot pattern projected by the spot projector and project a spot pattern or a flood pattern to the target object. After the liquid crystal receives the spot pattern projected by the spot projector, it projects the spot pattern or the flood pattern to the target object 20 according to the physical state controlled by the processor 13. Among them, the processor 13 controls the liquid crystal to be in a transparent state so that the emission module 11 projects the spot pattern to the target object 20; the processor 13 controls the liquid crystal to be in a diffuse state so that the emission module 11 projects the flood pattern to the target object 20.

[0049] It should be understood that in this embodiment, when the measurement distance is short and the device 10 requires a higher resolution, it is preferred to control the liquid crystal to be in a diffuse state, and the emission module 11 projects a flood pattern to the target object 20, so that the TOF pixel can collect a depth value with higher accuracy. Similarly, for example, for a long measurement distance, it is preferred to control the liquid crystal to be in a transparent state, and the emission module 11 projects a spot pattern to the target object 20, because the use of spot projection will concentrate the energy on the spot, and the distance that can be measured is farther than that of flood projection.

[0050] According to the depth measurement system provided by this embodiment, the acquisition module first generates an event signal by collecting the reflected light signal reflected by the target object through the event pixel array; the processor generates an event image according to the event signal, and sends a depth pixel activation instruction to the acquisition module when it recognizes that the event image includes a valid measurement object; the acquisition module then responds to the depth pixel activation instruction and collects the reflected light signal through the depth pixel array to generate an electrical signal; the processor finally calculates the depth value of the target object based on the electrical signal. Through the implementation of the scheme of this application, whether the depth measurement conditions are met is first detected through event pixels, and the depth measurement is turned on only when the conditions are met, which can reduce the power consumption of the transmitting module and the acquisition module, and at the same time reduce the memory occupied by redundant data.

[0051] In order to solve the problem that the distance measurement technology provided in the related art requires the depth measurement system to keep working all the time, resulting in high power consumption and high memory usage, the second embodiment of the present application provides a depth measurement method, which is applied to a depth measurement system including a transmitting module, a collection module and a processor. Figure 3 This is a basic flow chart of the depth measurement system provided in this embodiment. The depth measurement method includes the following steps:

[0052] Step 301: The transmitting module projects the transmitting light toward the target object;

[0053] Step 302: The acquisition module acquires the reflected light signal reflected by the target object through the event pixel array in the initial state, and generates an event signal according to the reflected light signal;

[0054] Step 303: The processor generates an event image according to the event signal, and sends a depth pixel activation instruction to the acquisition module when the target object in the event image is identified as a valid measurement object;

[0055] Step 304: the acquisition module responds to the depth pixel activation instruction sent by the processor, acquires the reflected light signal through the depth pixel array, and generates an electrical signal according to the reflected light signal;

[0056] Step 305: The processor calculates the depth value of the target object based on the electrical signal.

[0057] In one implementation of this embodiment, the acquisition module includes a switchable pixel array, and the switchable pixel array is an event pixel array in an initial state. Accordingly, the step of the acquisition module responding to the depth pixel activation instruction sent by the processor to acquire the reflected light signal through the depth pixel array includes: the acquisition module responding to the depth pixel activation instruction sent by the processor to control the event pixel array to switch to the depth pixel array; and acquiring the reflected light signal through the depth pixel array.

[0058] In one implementation of this embodiment, the depth measurement system further includes a distance sensor, and the acquisition module includes a plurality of depth pixel arrays with different measurement accuracies. Accordingly, the aforementioned processor generates an event image according to the event signal, and when the target object in the event image is identified as a valid measurement object, sends a depth pixel activation instruction to the acquisition module, including: the processor generates an event image according to the event signal, and when the target object in the event image is identified as a valid measurement object, sends a distance measurement instruction to the distance sensor; the distance sensor detects the distance value of the target object; the processor compares the distance value with a preset depth threshold, and selects a depth pixel array of corresponding measurement accuracy according to the comparison result, and then sends a depth pixel activation instruction corresponding to the selected depth pixel array.

[0059] In one implementation of this embodiment, the aforementioned step of sending a depth pixel activation instruction to the acquisition module includes: sending a first depth pixel activation instruction to the acquisition module. The aforementioned step of the acquisition module responding to the depth pixel activation instruction sent by the processor, collecting the reflected light signal through the depth pixel array, and generating an electrical signal according to the reflected light signal includes: the acquisition module responding to the first depth pixel activation instruction sent by the processor, collecting the reflected light signal through the first depth pixel array, and generating a first electrical signal according to the reflected light signal. Before the aforementioned step of the processor calculating the depth value of the target object based on the electrical signal, it also includes: the processor calculates the first depth value based on the first electrical signal, and compares the first depth value with a preset depth threshold; when the first depth threshold exceeds the range defined by the depth threshold, sending a second depth pixel activation instruction to the acquisition module; the acquisition module responding to the second depth pixel activation instruction sent by the processor, collecting the reflected light signal through the second depth pixel array, and generating a second electrical signal according to the reflected light signal. The aforementioned step of the processor calculating the depth value of the target object based on the electrical signal includes: calculating the second depth value based on the second electrical signal, and using the second depth value as the depth value of the target object.

[0060] In one implementation of this embodiment, the emission module includes a spot projector and a liquid crystal. Correspondingly, the step of the emission module projecting emission light to the target object includes: the spot projector provides output light; the liquid crystal triggers a corresponding physical state according to a resolution requirement indicator, and projects the emission light to the target object in a physical state based on the output light; wherein the physical state includes a diffuse state and a transparent state.

[0061] It should be noted that the depth measurement system in the first embodiment can be implemented based on the depth measurement method provided in this embodiment. Ordinary technical personnel in the relevant field can clearly understand that for the convenience and conciseness of description, the specific working process of the depth measurement method described in this embodiment can refer to the corresponding implementation in the aforementioned device embodiment, and will not be repeated here.

[0062] Based on the technical solution of the embodiment of the present application, the acquisition module first generates an event signal by collecting the reflected light signal reflected by the target object through the event pixel array; the processor generates an event image according to the event signal, and sends a depth pixel activation instruction to the acquisition module when it recognizes that the event image includes a valid measurement object; the acquisition module then responds to the depth pixel activation instruction and collects the reflected light signal through the depth pixel array to generate an electrical signal; the processor finally calculates the depth value of the target object based on the electrical signal. Through the implementation of the solution of the present application, whether the depth measurement conditions are met is first detected through event pixels, and the depth measurement is turned on only when the conditions are met, which can reduce the power consumption of the transmitting module and the acquisition module, and at the same time reduce the memory occupied by redundant data.

[0063] Figure 4 A terminal device is provided in the third embodiment of the present application. The terminal device can be used to implement the depth measurement method in the above embodiment, mainly including:

[0064] The memory 401, the processor 402, and the computer program 403 stored in the memory 401 and executable on the processor 402, the memory 401 and the processor 402 are connected via communication. When the processor 402 executes the computer program 403, the method in the aforementioned embodiment 2 is implemented. The number of processors may be one or more.

[0065] The memory 401 may be a high-speed random access memory (RAM) memory, or a non-volatile memory, such as a disk memory. The memory 401 is used to store executable program codes, and the processor 402 is coupled to the memory 401 .

[0066] Furthermore, the present application also provides a computer-readable storage medium, which may be provided in the terminal device in the above embodiments. Figure 4 Memory in the illustrated embodiment.

[0067] The computer readable storage medium stores a computer program, and when the program is executed by the processor, the depth measurement method in the aforementioned embodiment is implemented. Furthermore, the computer storable medium can also be a U disk, a mobile hard disk, a read-only memory (ROM), a RAM, a magnetic disk or an optical disk, and other media that can store program codes.

[0068] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0069] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0070] In addition, each functional module in each embodiment of the present application can be integrated into a processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The above integrated modules can be implemented in the form of hardware or software functional modules.

[0071] If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a readable storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned readable storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks.

[0072] It should be noted that, for the above-mentioned method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described action sequence, because according to the present application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0073] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0074] The above is a description of the depth measurement system and method provided in the present application. For technicians in this field, according to the ideas of the embodiments of the present application, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present application.

Claims

1. A depth measurement system, characterized in that: include: Transmitting module, acquisition module and processor; The emission module is used to project emission light toward the target object; The acquisition module is used to acquire the reflected light signal reflected by the target object through the event pixel array in an initial state, and generate an event signal according to the reflected light signal, and in response to the depth pixel activation instruction sent by the processor, acquire the reflected light signal through the depth pixel array, and generate an electrical signal according to the reflected light signal; wherein the depth pixel array includes a TOF pixel array; The processor is used to generate an event image according to the event signal, and when the target object in the event image is identified as a valid measurement object, send the depth pixel activation instruction to the acquisition module, and then calculate the depth value of the target object based on the electrical signal.

2. The depth measurement system according to claim 1, characterized in that: The acquisition module includes a switchable pixel array, and the switchable pixel array is the event pixel array in the initial state; When the acquisition module executes the function of acquiring the reflected light signal through the depth pixel array in response to the depth pixel activation instruction sent by the processor, it is specifically used to: In response to a depth pixel activation instruction sent by the processor, controlling the event pixel array to switch to a depth pixel array; The reflected light signal is collected by the depth pixel array.

3. The depth measurement system according to claim 1, characterized in that: The depth measurement system also includes a distance sensor, and the acquisition module includes a plurality of depth pixel arrays with different measurement accuracy; The distance sensor is used to detect the distance value of the target object; When executing the function of sending the depth pixel activation instruction to the acquisition module, the processor is specifically used to: Comparing the distance value with a preset depth threshold, and selecting the depth pixel array of corresponding measurement accuracy according to the comparison result; The depth pixel activation instruction corresponding to the selected depth pixel array is sent.

4. The depth measurement system according to claim 1, characterized in that: When the processor executes the function of sending the depth pixel activation instruction to the acquisition module and then calculating the depth value of the target object based on the electrical signal, it is specifically used to: Sending a first depth pixel activation instruction to the acquisition module; wherein the first depth pixel activation instruction is used to trigger the acquisition module to acquire a first electrical signal through a first depth pixel array; Calculating a first depth value based on the first electrical signal, and comparing the first depth value with a preset depth threshold; When the first depth value exceeds the range defined by the depth threshold, a second depth pixel activation instruction is sent to the acquisition module; wherein the second depth pixel activation instruction is used to trigger the acquisition module to acquire a second electrical signal through a second depth pixel array; A second depth value is calculated based on the second electrical signal, and the second depth value is used as the depth value of the target object.

5. The depth measurement system according to claim 4, characterized in that: The acquisition module includes a switchable pixel array and the second depth pixel array. The switchable pixel array is the event pixel array in the initial state. The first depth pixel activation instruction is specifically used to: trigger the acquisition module to switch the event pixel array to the first depth pixel array, and obtain a first electrical signal through the first depth pixel array.

6. The depth measurement system according to claim 3 or 4, characterized in that: The emission module is also used to: project emission light to calibration objects at different measurement distances within a preset measurement range; The acquisition module is also used to respectively acquire reflected light signals reflected back by the calibration object through a plurality of depth pixel arrays with different measurement accuracy, and generate calibration electrical signals according to the reflected light signals; The processor is further configured to respectively calculate calibrated depth values ​​according to the calibrated electrical signals corresponding to the depth pixel arrays of different measurement precisions, and determine the measurement distance corresponding to when the calibrated depth values ​​corresponding to different depth pixel arrays are equal as the depth threshold.

7. The depth measurement system according to any one of claims 1 to 5, characterized in that: The emission module includes a spot projector and a liquid crystal; The spot projector is used to provide output light; The liquid crystal is used to trigger a corresponding physical state according to a resolution requirement indicator, and to project emitted light to a target object in the physical state based on the output light; wherein the physical state includes a diffuse state and a transparent state.

8. A depth measurement method, applied to a depth measurement system including a transmitting module, a collecting module and a processor, characterized in that: include: The emission module projects emission light toward the target object; The acquisition module acquires the reflected light signal reflected by the target object through the event pixel array in the initial state, and generates an event signal according to the reflected light signal; The processor generates an event image according to the event signal, and sends a depth pixel activation instruction to the acquisition module when identifying that the target object in the event image is a valid measurement object; The acquisition module responds to the depth pixel activation instruction sent by the processor, acquires the reflected light signal through the depth pixel array, and generates an electrical signal according to the reflected light signal; wherein the depth pixel array includes a TOF pixel array; The processor calculates a depth value of the target object based on the electrical signal.

9. The depth measurement method according to claim 8, characterized in that: The acquisition module includes a switchable pixel array, and the switchable pixel array is the event pixel array in the initial state; The step of the acquisition module acquiring the reflected light signal through the depth pixel array in response to the depth pixel activation instruction sent by the processor includes: The acquisition module controls the event pixel array to switch to the depth pixel array in response to the depth pixel activation instruction sent by the processor, and acquires the reflected light signal through the depth pixel array.

10. The depth measurement method according to claim 8, characterized in that: The emission module includes a spot projector and a liquid crystal; The step of projecting emission light by the emission module toward the target object comprises: The spot projector provides output light; The liquid crystal triggers a corresponding physical state according to a resolution requirement indicator, and projects emitted light to a target object in the physical state based on the output light; wherein the physical state includes a diffuse state and a transparent state.

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