WO2022052365A1 - 图像采集系统、方法、设备及存储介质 - Google Patents

图像采集系统、方法、设备及存储介质 Download PDF

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Publication number
WO2022052365A1
WO2022052365A1 PCT/CN2020/138043 CN2020138043W WO2022052365A1 WO 2022052365 A1 WO2022052365 A1 WO 2022052365A1 CN 2020138043 W CN2020138043 W CN 2020138043W WO 2022052365 A1 WO2022052365 A1 WO 2022052365A1
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Prior art keywords
light
image
wavelength
original image
channel
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PCT/CN2020/138043
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English (en)
French (fr)
Inventor
黄进新
程敏
夏余
石昌寿
方光祥
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华为技术有限公司
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Publication of WO2022052365A1 publication Critical patent/WO2022052365A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/50—Constructional details
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/56—Cameras or camera modules comprising electronic image sensors; Control thereof provided with illuminating means
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/60—Control of cameras or camera modules
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/70—Circuitry for compensating brightness variation in the scene
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/70—Circuitry for compensating brightness variation in the scene
    • H04N23/74—Circuitry for compensating brightness variation in the scene by influencing the scene brightness using illuminating means
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/80—Camera processing pipelines; Components thereof

Definitions

  • the present application relates to the field of video surveillance, and in particular, to an image acquisition system, method, device and storage medium.
  • video surveillance has developed very rapidly and is widely used in many scenarios. For example, in traffic management scenarios, video surveillance can monitor all vehicles passing on the road in real time, and collect images of vehicles to obtain full-color images to identify vehicle information and face information in the vehicle.
  • the shooting environment needs to be supplemented during the day and night.
  • the combination of gas strobe lights and light emitting diode (LED) strobe lights is used to achieve supplementary light.
  • LED light emitting diode
  • Light in the daytime environment, the ambient light is relatively sufficient, and the strong light strobe generated by the gas strobe light does not have much impact on the driver and passengers, but in the night environment, the strong light strobe generated by the gas strobe light will produce extreme light. Large light pollution poses a serious hazard to traffic safety.
  • prism-based multi-spectral fusion technology which splits visible light and infrared light into two parts through prism lens.
  • one image sensor is used to sense visible light and output color image
  • the other image sensor is used to sense infrared light, output black and white image
  • the image processing module fuses the two images to output full color image.
  • visible light is mainly supplemented by LED strobe lights
  • infrared light is mainly supplemented by infrared gas strobe lights.
  • the collected image will have color cast, which may easily lead to the loss or error of local information in the image.
  • the implementation cost of the above-mentioned method is very high, and it needs to be equipped with a prism lens with high manufacturing cost, two Image sensor and multiple fill lights.
  • the infrared strobe light cannot effectively penetrate some coated windows, resulting in poor interior effect.
  • the infrared strobe has obvious red exposure and energy. Very strong, it will cause damage to the human eye, and in order to alleviate the color cast, the LED stroboscopic fill light will be very strong, so this solution does not fundamentally reduce light pollution.
  • the embodiments of the present application provide an image acquisition system, method, device, and storage medium, which can greatly reduce light pollution.
  • the technical solution is as follows:
  • an image acquisition system includes: a lens, an image sensor, a fill light, and an image processing unit.
  • an image sensor for photoelectric conversion of the light collected by the lens to generate an original image, and sending the original image to the image processing unit;
  • the fill light is used to fill light with first visible light in a low illumination environment, the wavelength range of the first visible light belongs to the wavelength range of 380nm to 680nm, and the first visible light corresponds to the wavelength light that the human eye is not sensitive to The light intensity is higher than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the first visible light;
  • the image processing unit is configured to perform white balance processing on the original image after receiving the original image.
  • the supplementary light when the target area is in a low illumination environment, the supplementary light can be supplemented with visible light that is relatively insensitive to the human eye, which can effectively reduce light pollution.
  • the image The processing unit performs white balance processing on the original image, so that the final output image will not have color cast.
  • the wavelength range of the first visible light is 400nm to 650nm.
  • the wavelength range of the wavelength light in which the human eye is insensitive is within the following wavelength bands: 400 nm to 480 nm, and 620 nm to 650 nm; the wavelength range of the wavelength light that the human eye is sensitive to is located within the following wavelength bands: 480nm to 620nm.
  • the wavelength light to which the human eye is insensitive refers to wavelength light that does not include green light; the wavelength light to which the human eye is sensitive refers to wavelength light that includes green light.
  • the wavelength light including green light as the wavelength light that the human eye is sensitive to, and then reducing the light intensity corresponding to this part of the wavelength light, that is, the light intensity corresponding to the green light, it is fully considered.
  • the human eye is more sensitive to green light, which can greatly reduce the damage to the human eye when filling light.
  • the sensitivity of the image sensor to green light is relatively low, so it will not unduly affect the image sensor's sensitivity to light. conversion function.
  • the image processing unit is configured to adjust the gray value of each channel in the original image.
  • adjusting the gray value of each channel in the original image refers to improving the gray value of at least one channel in the original image.
  • the image processing unit is used for:
  • the grayscale value of each channel is subjected to a linear contrast raising process.
  • the image processing unit is used for:
  • the gray value of each channel is counted to obtain the average gray value of each channel
  • gain processing is performed on the grayscale value of each channel.
  • the white balance processing of the original image is carried out in the following manner, the parameters of the white area in the original image are calibrated by the white area distribution model, and then the parameters of the white area in the original image are calibrated according to the calibrated parameters. Determine the white area, after determining the white area, then pull up the gray value distribution of each channel in the white area to balance to obtain the ideal white balance effect.
  • the image processing unit does not need to determine the white area in the original image, but directly adopts the method of linear contrast increase processing or gain processing.
  • the gray value of each channel in the original image is adjusted to obtain the ideal white balance effect, and the white area distribution model does not need to be used for parameter calibration, thus reducing the workload of data processing.
  • the gray value of each channel in the original image reaches a balanced state, and the resulting image is output. Color casts do not occur, improving image quality.
  • the supplementary light includes: a lamp body, a controller, a motor, a light source and a filter blade, the light source, the motor and the controller are all located inside the lamp body, and the controller is respectively connected with the motor and the light source , the filter blade is located at the opening of the lamp body, and is driven by the motor to realize the opening and closing operation; the controller controls the light source to emit light, and controls the motor to work; the light source is controlled by the controller to emit light; the motor is controlled by the The controller controls to drive the filter blade to close; when the filter blade is in the closed state, the filter blade filters the light emitted by the light source to transmit the first visible light.
  • the target area when the target area is imaged in a nighttime environment, the light emitted by the light source is filtered by controlling the closing of the filter blades in the supplementary light, and the first visible light, which is relatively insensitive to human eyes, is filtered.
  • the target area is supplemented with light, which greatly reduces the light pollution caused by the supplementary light when capturing images at night.
  • the supplementary light is also used to perform supplementary light with a second visible light in a normal illumination environment.
  • the wavelength range of the second visible light is 380nm to 680nm, and the second visible light is insensitive to the wavelength of light.
  • the corresponding light intensity is lower than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the second visible light.
  • the target area when the target area is imaged in the daytime environment, by controlling the opening of the filter blades in the supplementary light, the target area is supplemented with the second visible light, so that the target area can be supplemented in the daytime environment and the nighttime environment. It only needs to be supplemented by this supplementary light, which will not cause additional light pollution and greatly save costs.
  • an image acquisition method is provided.
  • the method is applied to an image acquisition system.
  • the image acquisition system includes: a lens, an image sensor, a fill light, and an image processing unit, and the method includes:
  • the lens collects the light of the target area
  • the image sensor photoelectrically converts the light collected by the lens to generate an original image, and sends the original image to the image processing unit;
  • the fill light uses the first visible light to fill in the light in a low illumination environment, the wavelength range of the first visible light belongs to the wavelength range of 380nm to 680nm, and the light intensity corresponding to the wavelength light that the human eye is not sensitive to in the first visible light is high The light intensity corresponding to the wavelength light to which the human eye is sensitive in the first visible light;
  • the image processing unit After receiving the original image, the image processing unit performs white balance processing on the original image.
  • the image acquisition method is applied to an image acquisition system, wherein when the target area is in a low illumination environment, the supplementary light uses visible light, which is relatively insensitive to the human eye, for supplementary light, which can effectively reduce light pollution.
  • the image processing unit performs white balance processing on the original image, so that the final output image will not have color cast.
  • the wavelength range of the first visible light is 400nm to 650nm.
  • the wavelength range of the wavelength light in which the human eye is insensitive is within the following wavelength bands: 400 nm to 480 nm, and 620 nm to 650 nm; the wavelength range of the wavelength light that the human eye is sensitive to is located within the following wavelength bands: 480nm to 620nm.
  • the wavelength light to which the human eye is insensitive refers to wavelength light that does not include green light; the wavelength light to which the human eye is sensitive refers to wavelength light that includes green light.
  • performing white balance processing on the original image includes: adjusting the gray value of each channel in the original image.
  • adjusting the gray value of each channel in the original image refers to improving the gray value of at least one channel in the original image.
  • white balance the original image including:
  • the grayscale value of each channel is subjected to a linear contrast raising process.
  • performing white balance processing on the original image including:
  • the gray value of each channel is counted to obtain the average gray value of each channel
  • gain processing is performed on the grayscale value of each channel.
  • the supplementary light includes: a lamp body, a controller, a motor, a light source and a filter blade, the light source, the motor and the controller are all located inside the lamp body, and the controller is respectively connected with the motor and the light source , the filter blade is located at the opening of the lamp body, and is driven by the motor to realize the opening and closing operation.
  • the fill light is filled with the first visible light in a low illumination environment, including:
  • the controller controls the light source to emit light, and controls the motor to work
  • the light source is controlled by the controller to emit light
  • the motor is controlled by the controller to drive the filter blade to close;
  • the filter blade When the filter blade is in a closed state, the filter blade filters the light emitted by the light source to transmit the first visible light.
  • the method further includes:
  • the fill light uses second visible light for fill light
  • the wavelength range of the second visible light is 380nm to 680nm
  • the light intensity corresponding to the wavelength light in the second visible light that the human eye is not sensitive to is lower than the The light intensity corresponding to the wavelength light to which the human eye is sensitive in the second visible light.
  • an image acquisition device comprising: an acquisition module, a conversion module, a light-filling module, and an image processing module;
  • the acquisition module is used to collect the light of the target area
  • the conversion module is used to perform photoelectric conversion on the light collected by the acquisition module to generate an original image, and send the original image to the image processing module;
  • the supplementary light module is used for supplementing light with first visible light in a low illumination environment, the wavelength range of the first visible light belongs to the wavelength range of 380 nm to 680 nm, and the wavelength light of the first visible light that the human eye is not sensitive to corresponds to The light intensity is higher than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the first visible light;
  • the image processing module is configured to perform white balance processing on the original image after receiving the original image.
  • the light-filling module can fill light with visible light that is relatively insensitive to human eyes when the target area is in a low-illumination environment, which can effectively reduce light pollution.
  • the image The processing module performs white balance processing on the original image, so that the final output image will not have color cast.
  • the wavelength range of the first visible light is 400nm to 650nm.
  • the wavelength range of the wavelength light in which the human eye is insensitive is within the following wavelength bands: 400 nm to 480 nm, and 620 nm to 650 nm; the wavelength range of the wavelength light that the human eye is sensitive to is located within the following wavelength bands: 480nm to 620nm.
  • the wavelength light to which the human eye is insensitive refers to wavelength light that does not include green light; the wavelength light to which the human eye is sensitive refers to wavelength light that includes green light.
  • the image processing module is used to adjust the gray value of each channel in the original image.
  • adjusting the gray value of each channel in the original image refers to improving the gray value of at least one channel in the original image.
  • the image processing module is used to:
  • the grayscale value of each channel is subjected to a linear contrast raising process.
  • the image processing module is used to:
  • the gray value of each channel is counted to obtain the average gray value of each channel
  • gain processing is performed on the grayscale value of each channel.
  • the supplementary light module includes: a lamp body, a controller, a motor, a light source and a filter blade, the light source, the motor and the controller are all located inside the lamp body, and the controller is respectively connected with the motor and the light source , the filter blade is located at the opening of the lamp body, and is driven by the motor to realize the opening and closing operation; the controller controls the light source to emit light, and controls the motor to work; the light source is controlled by the controller to emit light; the motor is controlled by the The controller controls to drive the filter blade to close; when the filter blade is in the closed state, the filter blade filters the light emitted by the light source to transmit the first visible light.
  • the supplementary light module is also used to perform supplementary light with a second visible light in a normal illumination environment, and the wavelength range of the second visible light is 380nm to 680nm, and the wavelength light of the second visible light that is insensitive to the human eye.
  • the corresponding light intensity is lower than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the second visible light.
  • an image acquisition device in a fourth aspect, includes a processor and a memory, the memory is used to store at least a piece of program code, the at least a piece of program code is loaded and executed by the processor, so that the image acquisition
  • the device implements the image acquisition method provided in the second aspect or any optional manner of the second aspect.
  • a computer-readable storage medium is provided, and the computer-readable storage medium is used to store at least one piece of program code, and the at least one piece of program code is loaded and executed by a processor, so that the image acquisition device realizes the above-mentioned second aspect Or the image acquisition method provided in any optional manner in the second aspect.
  • a computer program product or computer program includes program code, which, when run on an image capture device, causes the image capture device to perform the above-mentioned second aspect or the second aspect
  • the image acquisition methods provided in various optional implementations of .
  • FIG. 1 is a schematic diagram of an application scenario of an image acquisition system provided by an embodiment of the present application.
  • FIG. 2 is a schematic diagram of the architecture of an image acquisition system provided by an embodiment of the present application.
  • FIG. 3 is a schematic structural diagram of a fill light provided by an embodiment of the present application.
  • FIG. 5 is a schematic diagram of the relative visual acuity of a human eye provided by an embodiment of the present application.
  • FIG. 6 is a QE curve diagram of an image sensor provided by an embodiment of the present application.
  • FIG. 7 is a schematic diagram of a first visible light provided by an embodiment of the present application.
  • FIG. 8 is a schematic diagram of a second visible light provided by an embodiment of the present application.
  • FIG. 9 is a schematic diagram of a white balance processing method provided by an embodiment of the present application.
  • FIG. 10 is a schematic structural diagram of an image acquisition device provided by an embodiment of the present application.
  • FIG. 11 is a schematic structural diagram of an image acquisition device provided by an embodiment of the present application.
  • the image acquisition system provided by the embodiments of the present application can be applied to scenarios that require image acquisition, such as traffic management, community safety management, and event detection.
  • scenarios to which the image acquisition system and method of the embodiments of the present application can be applied include but are not limited to:
  • Scenario 1 Bayonet Scenario
  • FIG. 1 is a schematic diagram of an application scenario of an image acquisition system provided by an embodiment of the present application.
  • a bayonet device is usually installed on the road to realize real-time monitoring of all vehicles passing through the current road.
  • the image acquisition system of the equipment and the fill light includes a lens and an image sensor.
  • the fill light will fill the current road environment.
  • the road environment is imaged to obtain an image containing the vehicle currently passing through the bayonet device.
  • the supplementary light can be supplemented with visible light, which is relatively insensitive to the human eye, which greatly reduces light pollution and does not affect driving and riding.
  • the vision of the personnel ensures the traffic safety while the image is collected.
  • Scenario 2 Community access management scenario
  • video surveillance devices are usually installed at the entrances and exits of the community to monitor vehicles and people entering and leaving the community in real time.
  • the image acquisition system of the lamp, the camera equipment includes a lens and an image sensor.
  • the fill light will fill in the current community environment, and the camera equipment will collect the image of the vehicle or person, which is convenient for statistics.
  • the supplementary light can be supplemented with visible light, which is relatively insensitive to the human eye, which greatly reduces light pollution and does not affect access. The vision of people in the community or the occupants of the vehicle.
  • Spectrum is a pattern in which the dispersed monochromatic light is arranged in sequence according to the wavelength (or frequency) after the polychromatic light is split by a dispersion system (such as a prism and a grating).
  • the full name is optical spectrum.
  • the largest part of the spectrum, the visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye, and electromagnetic radiation in this wavelength range is called visible light.
  • Different wavelength ranges of light perceived by the human eye may have different colors, for example, light in the wavelength range of 490 nm (nanometers) to 580 nm is green light, light in the wavelength range of 620 nm to 600 nm is orange light, and so on. But the spectrum doesn't include all the colors that the human brain can visually distinguish, such as browns and pinks.
  • a special spectrum refers to a spectrum that is different from the ambient light spectrum and the general spectrum. The difference is that the wavelength range and energy ratio of each wavelength of this special spectrum are obviously different from the ambient light spectrum and the general spectrum.
  • the selection of range and energy ratio is based on improving the fill light efficiency of the image sensor, that is, under the condition of providing fill light with the same illuminance, the dazzling index of the human eye is greatly reduced.
  • the visual acuity characteristic refers to the characteristic that the human eye has different sensitivities to light of different wavelengths, that is, the human eye has different brightness perceptions for each color light with the same radiation power.
  • Image signal processing is to process the signal output by the image sensor, mainly including automatic exposure control (automatic exposure control, AEC), automatic gain control (automatic gain control, AGC), automatic white balance, color correction , lens shading correction, dead pixel removal, noise reduction, sharpening, and more.
  • automatic exposure control automatic exposure control
  • AGC automatic gain control
  • white balance automatic white balance
  • color correction lens shading correction
  • dead pixel removal dead pixel removal
  • noise reduction sharpening
  • the image sensor involved in the embodiments of the present application includes a charge-coupled device (CCD) image sensor. It also includes image sensors based on complementary metal oxide semiconductor (complementary metal oxide semiconductor, CMOS) processes, also known as CMOS image sensors (CMOS image sensors), which are used in network cameras, digital cameras and other electronic optical devices. Core components. Certainly, other types of image sensors may also be included in some embodiments, and the types of the involved image sensors are not limited in this embodiment of the present application.
  • CMOS complementary metal oxide semiconductor
  • CMOS image sensors CMOS image sensors
  • Image fusion is an image processing technology that uses a specific algorithm to synthesize two or more images into a new image.
  • the synthesized image has the excellent characteristics of the original image, such as brightness, sharpness, color, etc. .
  • Common image fusion techniques include the fusion of visible light images and infrared images.
  • Quantum efficiency is a factor that directly affects the photoelectric performance of image sensors, because any loss in photoelectric conversion efficiency directly reduces the signal-to-noise ratio (SNR). Its impact is two-fold, because when shot noise (square root of the signal) is the dominant noise source, QE is not only the dividend (signal) but also the divisor (noise) of the signal-to-noise ratio. Above this point, the CCD image sensor and the CMOS image sensor are at the same level, but the CCD image sensor has accumulated many years of technical process optimization in terms of QE improvement, and the QE improvement of the CMOS image sensor is relatively late.
  • RAW image format is the raw data that CMOS image sensor or CCD image sensor converts the captured light source signal into digital signal.
  • a RAW file is a file that records the raw information of the digital camera sensor and some metadata (such as shutter speed, aperture value, white balance, etc.) produced by the camera.
  • RAW is an unprocessed and uncompressed format, which can be conceptualized as "raw image encoded data" or more vividly as "digital negative”.
  • the types of RAW image formats include: RGGB, RYYB, RCCC, RCCB, RGBW, and CMYW.
  • RGB red green blue
  • ISP can convert RAW images of various formats to RGB format.
  • Luminous intensity refers to luminous intensity, which is referred to as luminous intensity or luminosity in photometry.
  • the physical quantity used to represent the luminous flux per unit solid angle in a given direction of the light source, the international unit is candela, symbol: cd, also known as candle light, branch light.
  • Light intensity is a physical term that refers to the luminous flux of visible light received per unit area.
  • illuminance the unit is lux (lux or lx), which is used to indicate the intensity of illumination and the amount of illumination on the surface area of an object.
  • Relative intensity refers to the energy ratio of the light intensity corresponding to different wavelengths to the total light intensity.
  • FIG. 2 is a schematic structural diagram of an image acquisition system provided by an embodiment of the present application.
  • the image acquisition system includes: a lens 201 , an image sensor 202 , a fill light 203 and an image processing unit 204 .
  • the lens 201 is used to collect the light of the target area
  • an image sensor 202 configured to perform photoelectric conversion on the light collected by the lens 201 to generate an original image, and send the original image to the image processing unit 204;
  • the fill light 203 is used to fill light with the first visible light in a low illumination environment.
  • the wavelength range of the first visible light belongs to the wavelength range of 380nm (nanometer) to 680nm, and the first visible light is insensitive to the wavelength of the human eye.
  • the light intensity corresponding to the light is higher than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the first visible light;
  • the image processing unit 204 is configured to perform white balance processing on the original image after receiving the original image.
  • the wavelength range of the first visible light is 400nm to 650nm.
  • the wavelength range of the wavelength light in which the human eye is insensitive is within the following wavelength bands: 400 nm to 480 nm, and 620 nm to 650 nm; the wavelength range of the wavelength light that the human eye is sensitive to is located within the following wavelength bands: 480nm to 620nm.
  • the wavelength light to which the human eye is insensitive refers to wavelength light that does not include green light; the wavelength light to which the human eye is sensitive refers to wavelength light that includes green light.
  • the image processing unit 204 is configured to adjust the gray value of each channel in the original image.
  • adjusting the gray value of each channel in the original image refers to improving the gray value of at least one channel in the original image.
  • the image processing unit 204 is used for:
  • the grayscale value of each channel is subjected to a linear contrast raising process.
  • the image processing unit 204 is used for:
  • the gray value of each channel is counted to obtain the average gray value of each channel
  • gain processing is performed on the grayscale value of each channel.
  • the supplementary light 203 is also used to perform supplementary light with a second visible light in a normal illumination environment.
  • the wavelength range of the second visible light is 380nm to 680nm, and the second visible light is insensitive to the wavelength of the human eye.
  • the light intensity corresponding to the light is lower than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the second visible light.
  • the supplementary light when the target area is in a low illumination environment, the supplementary light can be supplemented with visible light that is relatively insensitive to the human eye, which can effectively reduce light pollution.
  • the image The processing unit performs white balance processing on the original image, so that the final output image will not have color cast.
  • FIG. 3 is a schematic structural diagram of a fill light provided by an embodiment of the present application.
  • the fill light 203 includes: a lamp body 2031, a controller 2032, a motor 2033, a light source 2034 and a filter blade 2035, wherein the controller 2032, the motor 2033 and the light source 2034 are all located inside the lamp body 2031, The controller 2032 is respectively connected with the motor 2033 and the light source 2034.
  • the filter blade 2035 is located at the opening of the lamp body 2031, and is driven by the motor 2033 to realize the opening and closing operation. closure.
  • the controller 2032 is used to control the light source 2034 to emit light, and to control the motor 2033 to work;
  • the motor 2033 is used to be controlled by the controller 2032 to drive the filter blade 2035 to close;
  • the light source 2034 is used to emit light under the control of the controller 2032;
  • the filter blade 2035 is used to filter the light emitted by the light source 2034 when the filter blade 2035 is in a closed state, so as to transmit the first visible light, so that the first visible light is emitted to the target area to realize supplementary light to the target area.
  • FIG. 3 is only an exemplary schematic diagram of the structure of the fill light provided by the embodiment of the present application.
  • the positions of the above-mentioned components can be set according to the needs of the user.
  • the fill light The components of the lamp are not limited to the above-mentioned 2031 to 2035, and in practical applications, more components can be set according to the needs of users.
  • the embodiments of the present application do not limit the structure of the fill light.
  • FIG. 4 is a flowchart of an image acquisition method provided by an embodiment of the present application.
  • the image acquisition method is applied to the above-mentioned image acquisition system.
  • the image acquisition system includes: a lens, an image sensor, a fill light and an image processing unit.
  • the method includes the following steps:
  • the control unit determines that image acquisition needs to be performed on the target area.
  • the image acquisition system further includes a control unit, which can be configured to determine that the image acquisition needs to be performed on the target area to satisfy the image acquisition conditions, that is, step 401 is performed by the control unit.
  • the target area refers to the area where image acquisition needs to be performed.
  • the target area is an area within a preset distance from the lens, for example, the target area is an area within a range of 50m from the lens. The embodiment of the present application does not specifically limit the delimitation of the target area.
  • the control unit determines that image acquisition needs to be performed on the target area.
  • the image acquisition condition includes that the target object in the target area is at the target position.
  • the target object is a vehicle.
  • the image acquisition condition includes a moving object in the target area, for example, the moving object is a moving vehicle, bicycle and other means of transportation, and for another example, the moving object is a person whose action changes, and so on.
  • the image acquisition condition includes that the image acquisition time meets a time requirement, and the time requirement includes that the current time is a preset image acquisition time, for example, every 10 minutes, image acquisition is performed on the target area, and for example, during detection. After arriving at the vehicle, image acquisition is performed on the target area.
  • the image acquisition conditions can be set according to requirements, which is not limited in this embodiment of the present application.
  • the control unit determines that the target area is in a low illumination environment.
  • the low-illumination environment is an environment with an illumination intensity less than or equal to a preset threshold, or an environment in a target time period.
  • the low-illumination environment is also referred to as a nighttime environment.
  • the target time period is also a time period at night, such as 0:00 to 6:00, 18:00 to 24:00.
  • step 402 when the image acquisition system determines that the target area is in a low-light environment, it can be implemented by any one of the following methods 1 or 2:
  • Mode 1 The image acquisition system acquires the light intensity in the target area, and if the light intensity is less than or equal to a preset threshold, the image acquisition system determines that the target area is in a low-light environment.
  • the image acquisition system sets the preset threshold to 15 lux.
  • the image acquisition system obtains the current light intensity in the target area. If the obtained light intensity is less than or equal to 15 lux, it is determined that the target area is in In a low-illumination environment, if the obtained light intensity is greater than 15 lux, it is determined that the target area is in a normal illumination environment. It should be noted that, the embodiment of the present application does not specifically limit the setting of the preset threshold value of the light intensity and the judgment method.
  • Mode 2 The image acquisition system acquires the current time, and if the acquired current time is within the target time period, the image acquisition system determines that the target area is in a low illumination environment.
  • the image acquisition system presets the target time period as 0:00 to 6:00 and 18:00 to 24:00 every day. When the target area meets the image acquisition conditions, the image acquisition system acquires the current time. If the acquired current time is 22 If the current time obtained is 8 o'clock, it is determined that the target area is in a normal illumination environment. It should be noted that, the embodiment of the present application does not specifically limit the setting of the target time period.
  • this step 402 is performed by the control unit in the image acquisition system. After the control unit determines that the target area is in a low illumination environment, the control unit controls the lens to perform the following step 403 .
  • the control unit is a controller or a sensor.
  • the image acquisition system determines that the target area is in a low illumination environment, then in the low illumination environment, the target area is imaged, and the following steps 403 to 407 are performed.
  • control unit controls the lens to collect light in the target area.
  • the lens collects the light of the target area.
  • the embodiment of the present application does not specifically limit the manner in which the control unit controls the lens to collect the light of the target area.
  • the control unit controls the lens to collect the light of the target area through the hardware interface of the lens.
  • steps 401 and 402 are an optional implementation manner provided by this embodiment of the present application, that is, the control unit determines that the target area needs to be imaged, and then determines that the target area is in a low-light environment, Then, the control unit controls the lens to execute this step 403 .
  • the fill light uses the first visible light to fill in the light, the wavelength range of the first visible light belongs to the wavelength range of 380nm to 680nm, and the light intensity corresponding to the wavelength light that the human eye is not sensitive to in the first visible light is higher than the first visible light.
  • the first visible light is light emitted by the light source after being filtered by the filter blade in the fill light and can pass through the filter blade.
  • 380 nm to 680 nm may be expressed as (380 nm, 680 nm), or may be expressed as [380 nm, 680 nm], which is not limited in this embodiment of the present application.
  • the wavelength light that the human eye is not sensitive to there are two wavelengths of light, one is the wavelength light that the human eye is not sensitive to, and the other is the wavelength light that the human eye is sensitive to, wherein the wavelength light that the human eye is not sensitive to refers to excluding green light Wavelength light, the wavelength light that the human eye is not sensitive to can also be understood as light other than green light.
  • the wavelength light that the human eye is not sensitive to can also include a small amount of green light, because the green light energy is partially attenuated , the relative proportion of green light in the first visible light is reduced, so the human eye is relatively insensitive.
  • the wavelength light to which the human eye is sensitive refers to the wavelength light including green light, or it can be said that the wavelength light to which the human eye is sensitive is light including a large amount of green light, and the human eye is sensitive due to the large amount of green light.
  • the wavelength ranges of wavelength light that the human eye is not sensitive to are within the following wavelength bands: 400nm to 480nm, and 620nm to 650nm, which can be expressed as (400nm, 480nm) and (620nm, 650nm), or, It can also be expressed as [400nm, 480nm] and [620nm, 650nm]; the wavelength range that the human eye is sensitive to is within the following bands: 480nm to 620nm, which can be expressed as [480nm, 620nm], or Denoted as (480nm, 620nm).
  • the wavelength range of the wavelength light that the human eye is not sensitive to is within the following wavelength bands: 400nm to 450nm, and 600nm to 650nm, which can be expressed as (400nm, 450nm) and (600nm, 650nm), or , can also be expressed as [400nm, 450nm] and [600nm, 650nm]; the wavelength range where the human eye is sensitive to wavelength light is within the following bands: 450nm to 600nm, which can be expressed as [450nm, 600nm], or, also It can be expressed as (450nm, 600nm).
  • the embodiments of the present application do not limit the wavelength ranges of the wavelength light that the human eye is insensitive to and the wavelength light that the human eye is sensitive to. In practical applications, targeted settings can be made according to user needs.
  • FIG. 5 is a schematic diagram of a relative visual acuity of a human eye provided by an embodiment of the present application.
  • the figure is a curve obtained according to the experimental statistics of an observer with normal vision, and is divided into two visual acuity function curves of photopic vision and scotopic vision. It can be seen from the photopic visual acuity function curve that when the wavelength is located at 555nm, the relative visual acuity of the human eye is the highest. From the scotopic visual acuity function curve, it can be seen that when the wavelength is located at 507nm, the relative visual acuity of the human eye is the highest.
  • the wavelengths corresponding to the maximum value of the visual sensitivity function curve differ by nearly 50 nm. This is because there are two types of photosensitive cells on the retina of the human eye, one is rod cells and the other is cone cells. In this case, the two types of photosensitive cells acted respectively, resulting in deviations in the visual acuity function curve obtained under the two visual conditions of light and dark. From this, it can be concluded that the human eye is equivalent to a band-pass filter. change is more sensitive. As shown in the right figure in Figure 5, the visual sensitivity of the human eye to blue light is much lower than that of red light and green light. times), a considerable part of the three curves overlap. Under normal observation conditions, the human eye obtains the combined vision of the three and cannot distinguish their respective values.
  • FIG. 6 is a QE curve of an image sensor provided by an embodiment of the present application. It can be concluded from FIG. 6 that the relative intensity corresponding to red light is higher than the relative intensity corresponding to green light and blue light, Image sensors are more sensitive to light of higher relative intensity, so image sensors are more sensitive to red light than blue and green light.
  • the human eye is more sensitive to green light, and relatively insensitive to blue light and red light
  • the image sensor is more sensitive to red light, and is relatively sensitive to green and blue light. Therefore, in the visible light with a wavelength range of 380nm to 680nm, the light intensity corresponding to the wavelength light to which the human eye is sensitive, that is, the light intensity corresponding to the green light, is reduced to obtain the first visible light.
  • the sensitivity of the image sensor to green light is relatively low, the conversion function of the image sensor to light will not be excessively affected.
  • the wavelength range of the wavelength light corresponding to the light actually collected by the lens is 400nm to 650nm, therefore, in some embodiments, the wavelength range of the wavelength light of the first visible light is 400nm to 650nm.
  • the specific selection manner of the wavelength range of the first visible light is not limited in this embodiment of the present application.
  • the wavelength light between 400nm and 480nm and the wavelength between 620nm and 650nm are regarded as the wavelength light that the human eye is not sensitive to; the wavelength light between 480nm and 620nm is regarded as the wavelength light that the human eye is sensitive to.
  • the second selection method is to use the wavelength light between 400nm and 450nm and the wavelength light between 600nm and 650nm as the wavelength light that the human eye is not sensitive to; the wavelength light between 450nm and 600nm is the wavelength light that the human eye is sensitive to.
  • the first visible light in this step will be specifically described below by taking the above-mentioned second selection manner as an example.
  • FIG. 7 is a schematic diagram of a first visible light provided by an embodiment of the present application
  • FIG. 8 is a schematic diagram of a second visible light provided by an embodiment of the present application.
  • the visible light is also the light emitted by the light source in the fill light provided in the embodiment of the present application.
  • visible light in the wavelength range of 400nm to 650nm can be divided into three wavelengths of light, 400nm to 450nm, 450nm to 600nm, and 600nm to 650nm, and the light corresponding to these three wavelengths
  • the ratio of energy to the total light intensity is 1.42:1.56:1.
  • the wavelength light in the range of 450 to 600 nm is the wavelength light to which the human eye is sensitive
  • the wavelength light in the wavelength range of 400 nm to 450 nm and 600 nm to 650 nm is the wavelength light insensitive to the human eye.
  • visible light in the wavelength range of 400nm to 650nm can be divided into three wavelengths of light, namely 400 to 450nm, 450 to 600nm, and 600 to 650nm, and the light corresponding to these three wavelengths
  • the ratio of energy to the total light intensity is 1.42:4.68:1.
  • the wavelength light in the range of 450 to 600 nm is the wavelength light to which the human eye is sensitive
  • the wavelength light in the wavelength range of 400 nm to 450 nm and 600 nm to 650 nm is the wavelength light insensitive to the human eye.
  • the light intensity corresponding to the wavelength light of the second visible light that is insensitive to the human eye remains the same. It is lower than the light intensity corresponding to the wavelength light to which the human eye is sensitive, but in this case, because the energy ratio of the wavelength light to which the human eye is sensitive in the second visible light is reduced, the effect of reducing light pollution is also achieved.
  • the light intensity corresponding to the wavelength light in the first visible light that is insensitive to the human eye is higher than the light intensity corresponding to the wavelength light that the human eye is sensitive to in the first visible light
  • the light intensity corresponding to the wavelength light to which the human eye is sensitive in one visible light is lower than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the second visible light.
  • the following describes the supplementary light mode of the supplementary light in this step 404 .
  • the fill light includes: a lamp body, a controller, a motor, a light source and a filter blade, the light source, the motor and the controller are all located inside the lamp body, the controller is respectively connected with the motor and the light source, and the filter blade It is located at the opening of the lamp body, and is driven by a motor to realize the opening and closing operation.
  • the fill light method of the fill light specifically includes the following steps 1 to 4:
  • Step 1 The controller controls the light source to emit light and controls the motor to work.
  • Step 2 The light source is controlled by the controller to emit light.
  • Step 3 The motor is controlled by the controller to drive the filter blades to close.
  • the closing method of the filter blade is any of the following: First, the motor can drive the filter blade to close by pushing left and right at the opening of the lamp body. For details, please refer to the closing method of the automatic opening and closing door. Second, the motor can drive the filter blade to rotate up and down or left and right to close the opening of the lamp body. For details, please refer to the closing method of the louver sash. Thirdly, the motor can drive the filter blade to close by rotating clockwise or counterclockwise at the opening of the lamp body. For details, please refer to the opening method of the folding fan. It should be noted that, in practical applications, the closing methods of the filter blades are not limited to the above three methods, but can be set in any active mode. For setting, for example, considering cost requirements, aesthetic requirements, service life requirements, etc., the embodiments of the present application do not specifically limit the movement mode of the filter blades.
  • Step 4 When the filter blade is in a closed state, the light emitted by the light source is filtered to transmit the first visible light.
  • step 4 the filter blade is in a closed state, blocking the light source, so that the visible light emitted by the light source is emitted to the target area through the opening of the lamp body, so as to realize the supplementary light to the target area.
  • the filter blade is obtained by adding special dyes to the plastic or glass substrate or coating the optical film on the surface of the substrate based on the first visible light.
  • the filter blade When the filter blade is in the closed state, the light source in the fill light is blocked.
  • the filter blade can filter it, so that the first visible light passing through the filter blade is not sensitive to the human eye.
  • the light intensity corresponding to the wavelength light is higher than the light intensity corresponding to the wavelength light to which the human eye is sensitive, so that the supplementary light can perform supplementary light with the first visible light.
  • the embodiments of the present application do not specifically limit the specific material, manufacturing method, and shape parameters of the filter blade. In practical applications, the filter blade can be manufactured according to the needs of users.
  • the filter blade filters the visible light emitted by the light source, that is, it cannot filter the visible light within a certain value range.
  • the filter blade is set to filter visible light in the wavelength range of 450nm to 600nm, in fact, the filter blade may filter visible light between 440nm and 610nm when filtering. Therefore, it should be known that any visible light similar to or similar to the first visible light provided by the embodiments of the present application is within the protection scope of the embodiments of the present application.
  • the illumination intensity of the second visible light provided by the light source can be increased by increasing the power of the light source in the fill light. For example, if the illumination intensity of the second visible light is increased to 100 lux, even if the second visible light is filtered by the filter blade, the illumination intensity of the first visible light emitted by the fill light to the target area is relatively high, which can reach 60 lux. Under the same light intensity, the target area can be better filled with light, so that the lens can capture a clearer image, and the human eye is insensitive to the first visible light, so even if the fill light uses the first visible light to illuminate the target The area is filled with light, and it will not stimulate the human eyes. Therefore, the image acquisition system can protect the human eyes while achieving the ideal fill light effect.
  • steps 403 and 404 are performed synchronously, that is, when the lens collects light on the target area, the fill light uses the first visible light to fill the target area with light.
  • the image sensor performs photoelectric conversion on the light collected by the lens to generate an original image.
  • the original image refers to a RAW image directly generated by an image sensor based on light collected by a lens in a low-light environment.
  • the image sensor sends the original image to the image processing unit.
  • the image processing unit After receiving the original image, the image processing unit performs white balance processing on the original image.
  • the white balance processing refers to adjusting the grayscale values of each channel in the original image, so that the grayscale values of each channel in the original image reach a balanced state.
  • each channel refers to an R channel, a G channel, and a B channel.
  • the white balance processing includes any of the following processing methods:
  • the first processing method is to linearly increase the contrast of the original image. It includes the following steps 4071 to 4073:
  • Step 4071 The image processing unit obtains the gray value of each channel in the original image based on the original image.
  • Step 4072 The image processing unit performs histogram statistics on the grayscale values of each channel to obtain the maximum grayscale value and the minimum grayscale value of each channel.
  • the maximum gray value and the minimum gray value are the maximum gray value and the minimum gray value of each channel under the statistical threshold.
  • the gray values in the figure are in the order from low to high, and the total gray value corresponding to the number of pixels in the first interval is the minimum gray value; the gray value in the figure is the minimum gray value; In the order from high to low, the total gray value corresponding to the number of pixels in the second interval is the maximum gray value.
  • the first interval and the second interval are set in the form of percentages, for example, the first interval and the second interval are both set as the top 0.5%, that is, for the histogram of one channel, the gray value in the figure is based on the In the order from low to high, the gray values corresponding to the first 0.5% of the pixels are accumulated to obtain the minimum gray value; the gray values in the figure are in the order from high to low, and the first 0.5% of the pixels are corresponding to the number of pixels.
  • the grayscale values are accumulated to obtain the maximum grayscale value.
  • the embodiments of the present application do not limit the specific setting manners of the first interval and the second interval.
  • Step 4073 The image processing unit performs linear contrast enhancement processing on the gray value of each channel based on the maximum gray value and the minimum gray value.
  • the image processing unit obtains the gray value of the R channel in the original image, makes histogram statistics on the gray value of the R channel, and then determines the lowest gray value V min and the highest gray value V max in the histogram, based on For these two grayscale values, the grayscale value of the R channel is subjected to a linear contrast enhancement process according to the following formula (1).
  • V' CLIP(NMAX ⁇ ( VVmin )/( Vmax - Vmin ), 0, NMAX) (1)
  • V represents the gray value before pulling up
  • V′ represents the gray value after pulling up
  • the CLIP(x, min, max) function indicates that x is limited to between min and max, that is, NMAX ⁇ ( VVmin )/( Vmax - Vmin ) is defined between 0 and NMAX, where NMAX represents the theoretical maximum value of the data domain.
  • the second processing method is to perform gain processing on the original image. Specifically, it includes the following steps 407A to 407C:
  • Step 407A the image processing unit acquires the gray value of each channel in the first snapshot image based on the first snapshot image.
  • Step 407B The image processing unit counts the grayscale values of each channel to obtain the average grayscale value of each channel.
  • the image processing unit sums the gray values of each channel respectively, and then calculates the average gray value of each channel as:
  • Step 407C The image processing unit performs gain processing on the gray value of each channel based on the average gray value of each channel.
  • the image processing unit performs gain processing on the gray value of each channel according to the following formulas (2) to (4).
  • Formula (2) to formula (4) are:
  • the above-mentioned gain processing on the original image is to improve the gray value of at least one channel.
  • the above-mentioned gain processing process is a process of increasing the gray value of the G channel and the B channel.
  • the user can perform white balance processing on the original image as required, which is not limited to the above two white balance processing methods, which are not limited in the embodiments of the present application.
  • the image processing unit performs white balance processing on the original image, so that the grayscale values of each channel in the original image reach a balanced state, so that the output image will not have color cast, and the image quality is improved.
  • the target area is filled with the first visible light that is relatively insensitive to human eyes, and then the obtained original image White balance processing is performed to obtain high-quality full-color images without color cast, which greatly reduces the light pollution generated by the supplementary light during nighttime image capture.
  • the control unit determines that the target area is in a normal illumination environment.
  • the normal illumination environment is an environment where the illumination intensity is greater than a preset threshold, or an environment that is not in a target time period. In some embodiments, the normal illumination environment is also referred to as a daytime environment.
  • the image acquisition system acquires the illumination intensity in the target area, and if the illumination intensity is greater than a preset threshold, the image acquisition system determines that the target area is in a normal illumination environment.
  • the image acquisition system acquires the current time, and if the acquired current time is not within the target time period, the target area is in a normal illumination environment at this time.
  • this step 408 is performed by the control unit in the image acquisition system. After the control unit determines that the target area is in a normal illumination environment, the control unit controls the lens to perform the following step 409 .
  • the control unit is a controller or a sensor.
  • the image acquisition system determines that the target area is in a normal illumination environment, then in the normal illumination environment, image acquisition is performed on the target area, and the following steps 409 to 413 are executed.
  • control unit controls the lens to collect the light of the target area.
  • control unit controls the lens to capture the light in the target area
  • the fill light is filled with second visible light, the wavelength range of the second visible light is 380nm to 680nm, and the light intensity corresponding to the wavelength light that the human eye is not sensitive to in the second visible light is lower than that in the second visible light.
  • the second visible light is the light emitted by the light source in the fill light
  • the wavelength range of the second visible light can be expressed as (380nm, 680nm), or can be expressed as [380nm, 680nm], this application
  • the embodiment does not limit this.
  • the selection methods of the wavelength light insensitive to the human eye and the wavelength light sensitive to the human eye are similar to those in the above-mentioned step 404, and thus are not repeated here.
  • the second visible light in this step 410 will be specifically described below by taking the second selection manner shown in the foregoing step 404 as an example.
  • the wavelength light in the range of 450 to 600 nm is the wavelength light to which the human eye is sensitive
  • the wavelength light in the wavelength range of 400 nm to 450 nm and 600 nm to 650 nm is the wavelength light insensitive to the human eye.
  • the following describes the supplementary light method of the supplementary light in this step.
  • the supplementary light method of the supplementary light specifically includes the following steps 1 to 4:
  • Step 1 The controller controls the light source to emit light and controls the motor to work.
  • Step 2 The light source is controlled by the controller to emit light.
  • Step 3 The motor is controlled by the controller to drive the filter blades to open.
  • the opening method of the filter blade is any one of the following: First, the motor can drive the filter blade to open by pushing left and right at the opening of the lamp body. For details, please refer to the opening method of the automatic opening and closing door. Second, the motor can drive the filter blade to rotate up and down or left and right to open the opening of the lamp body. For details, please refer to the opening method of the shutter sash. Third, the motor can drive the filter blade to open in a clockwise or counterclockwise rotation at the opening of the lamp body. For details, please refer to the closing method of the folding fan. It should be noted that, in practical applications, the opening methods of the filter blades are not limited to the above three methods, but can be set in any active mode. For setting, for example, considering cost requirements, aesthetic requirements, service life requirements, etc., the embodiments of the present application do not specifically limit the movement mode of the filter blades.
  • Step 4 When the filter blade is in the open state, the light source is not blocked, and the second visible light emitted by the light source is emitted to the target area through the opening of the lamp body, so as to realize the supplementary light to the target area.
  • the fill light provides high-intensity fill light in a normal illumination environment, that is, a daytime environment, and uses second visible light for fill light, for example, the light intensity is 20,000 lux.
  • steps 409 and 410 are performed synchronously, that is, when the lens collects light on the target area, the fill light uses the second visible light to fill the target area with light.
  • the image sensor performs photoelectric conversion on the light collected by the lens to generate an original image.
  • the image sensor sends the original image to the image processing unit.
  • the image processing unit After receiving the original image, the image processing unit performs conventional image processing on the original image.
  • the conventional image processing refers to performing image processing on the original image according to the default image processing manner.
  • the embodiments of the present application do not specifically limit the image processing manner.
  • the above steps 401 to 413 control the opening and closing of the filter blades in the supplementary light, so that the supplementary light only needs to be supplemented by this supplementary light in both the daytime environment and the nighttime environment, which will not cause additional light pollution, and greatly reduce the amount of light pollution. Cost savings.
  • the fill light uses the first visible light to fill in the light, and the first visible light passes through the filter blade in the fill light to the light source.
  • the emitted light is filtered, and it is a kind of visible light that the human eye is relatively insensitive, so it can effectively reduce light pollution. No color cast will occur; when the target area is in a normal illumination environment, the fill light will use the second visible light to fill in the light.
  • This second visible light is the light directly emitted by the light source of the fill light, which can provide high-intensity compensation.
  • Light through the above method, only one fill light can be used for targeted fill light in the daytime environment and the nighttime environment, which not only reduces light pollution, but also saves costs.
  • FIG. 10 is a schematic structural diagram of an image acquisition apparatus provided by an embodiment of the present application.
  • the image acquisition apparatus is used to execute the steps in the execution of the above image acquisition method.
  • the image acquisition apparatus 1000 includes: an acquisition module 1001 , a conversion module 1002, light supplement module 1003 and image processing module 1004;
  • the collection module 1001 is used for collecting the light of the target area
  • a conversion module 1002 configured to perform photoelectric conversion on the light collected by the acquisition module to generate an original image, and send the original image to the image processing module;
  • the supplementary light module 1003 is used for supplementing light with a first visible light in a low illumination environment, the wavelength range of the first visible light belongs to the wavelength range of 380nm to 680nm, and the wavelength light of the first visible light that is insensitive to the human eye corresponds to The light intensity is higher than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the first visible light;
  • the image processing module 1004 is configured to perform white balance processing on the original image after receiving the original image.
  • the wavelength range of the first visible light is 400nm to 650nm.
  • the wavelength range of the wavelength light in which the human eye is insensitive is within the following wavelength bands: 400 nm to 480 nm, and 620 nm to 650 nm; the wavelength range of the wavelength light that the human eye is sensitive to is located within the following wavelength bands: 480nm to 620nm.
  • the wavelength light to which the human eye is insensitive refers to wavelength light that does not include green light; the wavelength light to which the human eye is sensitive refers to wavelength light that includes green light.
  • the image processing module 1004 is configured to adjust the gray value of each channel in the original image.
  • adjusting the gray value of each channel in the original image refers to improving the gray value of at least one channel in the original image.
  • the image processing module 1004 is used for:
  • the grayscale value of each channel is subjected to a linear contrast raising process.
  • the image processing module 1004 is used for:
  • the gray value of each channel is counted to obtain the average gray value of each channel
  • gain processing is performed on the grayscale value of each channel.
  • the supplementary light module 1003 includes: a lamp body, a controller, a motor, a light source and a filter blade, the light source, the motor and the controller are all located inside the lamp body, and the controller is respectively connected with the motor and the light source
  • the filter blade is located at the opening of the lamp body, and is driven by the motor to realize the opening and closing operation; the controller controls the light source to emit light, and controls the motor to work; the light source is controlled by the controller to emit light; the motor is controlled by the controller to emit light; The controller controls and drives the filter blade to close; when the filter blade is in the closed state, the filter blade filters the light emitted by the light source to transmit the first visible light.
  • the supplementary light module 1003 is also used to perform supplementary light with a second visible light in a normal illumination environment.
  • the wavelength range of the second visible light is 380nm to 680nm, and the second visible light is insensitive to the wavelength light of the human eye.
  • the corresponding light intensity is lower than the light intensity corresponding to the wavelength light to which the human eye is sensitive in the second visible light.
  • the light-filling module can fill light with visible light that is relatively insensitive to human eyes when the target area is in a low-illumination environment, which can effectively reduce light pollution.
  • the image The processing module performs white balance processing on the original image, so that the final output image will not have color cast.
  • FIG. 11 is a schematic structural diagram of an image acquisition device provided by an embodiment of the present application.
  • the image acquisition device 1100 may vary greatly due to different configurations or performances, and includes one or more processors 1101 and one or more The memory 1102, wherein the memory 1102 stores at least one piece of program code, and the at least one piece of program code is loaded and executed by the processor 1101 to implement the operations performed by the image acquisition system in the above method embodiments.
  • the image capture device 1100 can also have components such as a wired or wireless network interface, a keyboard, and an input and output interface for input and output.
  • the image capture device 1100 also includes other components for realizing device functions, which will not be repeated here. .
  • a computer-readable storage medium such as a memory including program codes, is also provided, and the program codes can be executed by a processor in the terminal to complete the image acquisition method in the foregoing embodiments.
  • the computer-readable storage medium is read-only memory (ROM), random access memory (RAM), compact disc read-only memory (CD-ROM), magnetic tape , floppy disks and optical data storage devices.
  • first, second and other words are used to distinguish the same or similar items with basically the same function and function, and it should be understood that between “first”, “second” and “nth” There are no logical or timing dependencies, and no restrictions on the number and execution order. It will also be understood that, although the following description uses the terms first, second, etc. to describe various elements, these elements should not be limited by the terms. These terms are only used to distinguish one element from another. For example, a first image may be referred to as a second image, and, similarly, a second image may be referred to as a first image, without departing from the scope of various described examples. Both the first image and the second image may be images, and in some cases, may be separate and distinct images.
  • the term “if” may be interpreted to mean “when” or “upon” or “in response to determining” or “in response to detecting.”
  • the phrases “if it is determined" or “if a [statement or event] is detected” can be interpreted to mean “when determining" or “in response to determining... ” or “on detection of [recited condition or event]” or “in response to detection of [recited condition or event]”.

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Abstract

一种图像采集系统、方法、设备及存储介质，属于视频监控领域。该图像采集系统包括：镜头、图像传感器、补光灯以及图像处理单元，其中，该补光灯能够在目标区域处于低照度环境下时，以人眼相对不敏感的可见光进行补光，这样可以有效降低光污染，同时，基于这种补光方式，由图像处理单元对原始图像进行白平衡处理，使得最终输出的图像不会发生偏色。

Description

图像采集系统、方法、设备及存储介质
本申请要求于2020年09月10日提交的申请号为202010945914.0、发明名称为“获取图像的方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
本申请要求于2020年12月16日提交的申请号为202011488166.4、发明名称为“图像采集系统、方法、设备及存储介质”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及视频监控领域，特别涉及一种图像采集系统、方法、设备及存储介质。
背景技术
近年来，视频监控发展非常迅速，广泛应用于许多场景中。例如，在交通管理场景中，采用视频监控能够实时监控道路中通过的所有车辆，并对车辆进行图像采集，得到全彩图像，以识别车辆信息和车内的人脸信息。通常基于视频监控对车辆进行图像采集时，在白天和夜间都需要对所拍摄的环境进行补光，一般通过气体爆闪灯和发光二极管(light emitting diode，LED)频闪灯的结合来实现补光，在白天环境下，环境光比较充足，气体爆闪灯产生的强光爆闪对驾乘人员没有太大影响，但在夜间环境下，气体爆闪灯产生的强光爆闪会产生极大的光污染，对交通安全构成严重的危害。
在相关技术中，为了去除夜间强光爆闪，降低光污染，基于视频监控进行图像采集时通常采用以下方法：基于棱镜的多光谱融合技术，通过棱镜镜头分光，将可见光和红外光分别分离到两个图像传感器上，一个图像传感器用于感可见光，输出彩色路图像，另一个图像传感器用于感红外光，输出黑白路图像，然后由图像处理模块将两路图像进行融合，输出全彩图像。其中，可见光主要通过LED频闪灯补光，红外光主要通过红外气体爆闪灯补光。
然而，上述多光谱融合技术方案，所采集到的图像会发生偏色，容易导致图像中局部信息缺失或错误，而且，上述方法的实施成本很高，需要配套高制造成本的棱镜镜头、两个图像传感器以及多个补光灯，另外，采用上述方法进行图像采集时，红外爆闪灯无法有效穿透一些镀膜的车窗，导致车内效果差，同时红外爆闪有明显的红曝且能量很强，对人眼会产生伤害，而且为了缓解偏色，LED频闪补光会很强，因此该方案并没有从根本上降低光污染。
发明内容
本申请实施例提供了一种图像采集系统、方法、设备及存储介质，能够极大地降低光污染。所述技术方案如下：
第一方面，提供了一种图像采集系统，该系统包括：包括：镜头、图像传感器、补光灯以及图像处理单元。
镜头，用于采集目标区域的光线；
图像传感器，用于对镜头采集的光线进行光电转换以生成原始图像，并将该原始图像发送至图像处理单元；
补光灯，用于在低照度环境下，以第一可见光进行补光，该第一可见光的波长范围属于380nm至680nm的波长范围，该第一可见光中人眼不敏感的波长光所对应的光强高于该第一可见光中人眼敏感的波长光所对应的光强；
图像处理单元，用于在接收到该原始图像后，对该原始图像进行白平衡处理。
在该图像采集系统中，补光灯能够在目标区域处于低照度环境下时，以人眼相对不敏感的可见光进行补光，这样可以有效降低光污染，同时，基于这种补光方式，由图像处理单元对原始图像进行白平衡处理，使得最终输出的图像不会发生偏色。
可选地，该第一可见光的波长范围为400nm至650nm。
可选地，该人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm；该人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm。
可选地，该人眼不敏感的波长光是指不包括绿光的波长光；该人眼敏感的波长光是指包括绿光的波长光。
基于上述可选地实现方式，通过将包括绿光的波长光选为人眼敏感的波长光，然后降低这部分波长光所对应的光强，也即是绿光所对应的光强，充分考虑到了人眼对绿光更为敏感，这样可以极大降低补光时对人眼产生的伤害，同时，图像传感器对绿光的敏感度相对不高，因此，也不会过度影响图像传感器对光线的转换功能。
可选地，该图像处理单元，用于对该原始图像中各个通道的灰度值进行调整。
可选地，对原始图像中各个通道的灰度值进行调整是指对原始图像中至少一个通道的灰度值进行提升。
可选地，该图像处理单元，用于：
基于该原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行直方图统计，得到该各个通道的最大灰度值和最小灰度值；
基于该最大灰度值和最小灰度值，对该各个通道的灰度值进行对比度线性拉升处理。
可选地，该图像处理单元，用于：
基于该原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行统计，得到该各个通道的平均灰度值；
基于该平均灰度值，对该各个通道的灰度值进行增益处理。
在相关技术中，对拍摄环境进行补光后，对原始图像进行白平衡处理时采用以下方式，通过白区分布模型对原始图像中白区的参数进行标定，然后按照标定的参数在原始图像中确定白区，在确定白区后，再将白区中各个通道的灰度值分布拉升到均衡来获得理想的白平衡效果。而基于上述可选地实现方式，在采用第一可见光对目标区域进行补光后，图像处理单元不需要确定原始图像中的白区，而是直接采用对比度线性拉升处理或增益处理的方式，对原始图像中各个通道的灰度值进行调整，以获得理想的白平衡效果，且不需要使用白区分布模型进行参数标定，从而减少了数据处理的工作量。
基于上述可选地实现方式，通过对原始图像进行白平衡处理，也即是对各个通道的灰度值进行调整，使得原始图像中各个通道的灰度值达到均衡状态，由此输出得到的图像不会发生偏色，提高了图像质量。
可选地，该补光灯包括：灯体、控制器、电机、光源以及滤光叶片，该光源、电机以及该控制器均位于该灯体内部，该控制器分别与该电机和该光源连接，该滤光叶片位于该灯体的开口处，由该电机驱动实现开合操作；该控制器控制该光源发光，并控制该电机工作；该光源受到该控制器控制进行发光；该电机受到该控制器控制，驱动该滤光叶片关闭；该滤光叶片在该滤光叶片处于关闭状态下，对该光源发出的光线进行过滤，以透过该第一可见光。
基于上述可选地实现方式，在夜间环境下对目标区域进行图像采集时，通过控制补光灯中滤光叶片的关闭，对光源发出的光线进行过滤，以人眼相对不敏感的第一可见光对目标区域进行补光，大大降低了夜间图像采集时由补光灯补光时产生的光污染。
可选地，该补光灯，还用于在正常照度环境下，以第二可见光进行补光，该第二可见光的波长范围为380nm至680nm，该第二可见光中人眼不敏感的波长光所对应的光强低于该第二可见光中人眼敏感的波长光所对应的光强。
基于上述可选地实现方式，在白天环境下对目标区域进行图像采集时，通过控制补光灯中滤光叶片的打开，以第二可见光对目标区域进行补光，实现在白天环境和夜间环境下都只需通过这一个补光灯进行补光，不会造成额外的光污染，也大大节约了成本。
第二方面，提供了一种图像采集方法，该方法应用于图像采集系统，该图像采集系统包括：镜头、图像传感器、补光灯以及图像处理单元，该方法包括：
镜头采集目标区域的光线；
图像传感器对镜头采集的光线进行光电转换以生成原始图像，并将原始图像发送至图像处理单元；
补光灯在低照度环境下，以第一可见光进行补光，该第一可见光的波长范围属于380nm至680nm的波长范围，该第一可见光中人眼不敏感的波长光所对应的光强高于该第一可见光中人眼敏感的波长光所对应的光强；
图像处理单元在接收到该原始图像后，对该原始图像进行白平衡处理。
该图像采集方法应用于图像采集系统，其中，由补光灯在目标区域处于低照度环境下时，以人眼相对不敏感的可见光进行补光，这样可以有效降低光污染，同时，基于这种补光方式，由图像处理单元对原始图像进行白平衡处理，使得最终输出的图像不会发生偏色。
可选地，该第一可见光的波长范围为400nm至650nm。
可选地，该人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm；该人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm。
可选地，该人眼不敏感的波长光是指不包括绿光的波长光；该人眼敏感的波长光是指包括绿光的波长光。
可选地，对原始图像进行白平衡处理，包括：对原始图像中各个通道的灰度值进行调整。
可选地，对原始图像中各个通道的灰度值进行调整是指对原始图像中至少一个通道的灰度值进行提升。
可选地，对原始图像进行白平衡处理，包括：
基于原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行直方图统计，得到该各个通道的最大灰度值和最小灰度值；
基于该最大灰度值和最小灰度值，对该各个通道的灰度值进行对比度线性拉升处理。
可选地，该对该原始图像进行白平衡处理，包括：
基于该原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行统计，得到该各个通道的平均灰度值；
基于该平均灰度值，对该各个通道的灰度值进行增益处理。
可选地，该补光灯包括：灯体、控制器、电机、光源以及滤光叶片，该光源、电机以及该控制器均位于该灯体内部，该控制器分别与该电机和该光源连接，该滤光叶片位于该灯体的开口处，由该电机驱动实现开合操作，该补光灯在低照度环境下，以第一可见光进行补光，包括：
该控制器控制该光源发光，并控制该电机工作；
该光源受到该控制器控制进行发光；
该电机受到该控制器控制，驱动该滤光叶片关闭；
该滤光叶片在该滤光叶片处于关闭状态下，对该光源发出的光线进行过滤，以透过该第一可见光。
可选地，该方法还包括：
该补光灯在正常照度环境下，以第二可见光进行补光，该第二可见光的波长范围为380nm至680nm，该第二可见光中人眼不敏感的波长光所对应的光强低于该第二可见光中人眼敏感的波长光所对应的光强。
第三方面，提供了一种图像采集装置，该装置包括：采集模块、转换模块、补光模块以及图像处理模块；
该采集模块，用于采集目标区域的光线；
该转换模块，用于对该采集模块采集的光线进行光电转换以生成原始图像，并将该原始图像发送至该图像处理模块；
该补光模块，用于在低照度环境下，以第一可见光进行补光，该第一可见光的波长范围属于380nm至680nm的波长范围，该第一可见光中人眼不敏感的波长光所对应的光强高于该第一可见光中人眼敏感的波长光所对应的光强；
该图像处理模块，用于在接收到该原始图像后，对该原始图像进行白平衡处理。
在该图像采集装置中，补光模块能够在目标区域处于低照度环境下时，以人眼相对不敏感的可见光进行补光，这样可以有效降低光污染，同时，基于这种补光方式，由图像处理模块对原始图像进行白平衡处理，使得最终输出的图像不会发生偏色。
可选地，该第一可见光的波长范围为400nm至650nm。
可选地，该人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm；该人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm。
可选地，该人眼不敏感的波长光是指不包括绿光的波长光；该人眼敏感的波长光是指包括绿光的波长光。
可选地，该图像处理模块用于对原始图像中各个通道的灰度值进行调整。
可选地，对原始图像中各个通道的灰度值进行调整是指对原始图像中至少一个通道的灰度值进行提升。
可选地，该图像处理模块用于：
基于原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行直方图统计，得到该各个通道的最大灰度值和最小灰度值；
基于该最大灰度值和最小灰度值，对该各个通道的灰度值进行对比度线性拉升处理。
可选地，该图像处理模块用于：
基于该原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行统计，得到该各个通道的平均灰度值；
基于该平均灰度值，对该各个通道的灰度值进行增益处理。
可选地，该补光模块包括：灯体、控制器、电机、光源以及滤光叶片，该光源、电机以及该控制器均位于该灯体内部，该控制器分别与该电机和该光源连接，该滤光叶片位于该灯体的开口处，由该电机驱动实现开合操作；该控制器控制该光源发光，并控制该电机工作；该光源受到该控制器控制进行发光；该电机受到该控制器控制，驱动该滤光叶片关闭；该滤光叶片在该滤光叶片处于关闭状态下，对该光源发出的光线进行过滤，以透过该第一可见光。
可选地，该补光模块还用于在正常照度环境下，以第二可见光进行补光，该第二可见光的波长范围为380nm至680nm，该第二可见光中人眼不敏感的波长光所对应的光强低于该第二可见光中人眼敏感的波长光所对应的光强。
第四方面，提供了一种图像采集设备，该图像采集设备包括处理器和存储器，该存储器用于存储至少一段程序代码，该至少一段程序代码由该处理器加载并执行，以使得该图像采集设备实现上述第二方面或第二方面中任一种可选方式所提供的图像采集方法。
第五方面，提供了一种计算机可读存储介质，该计算机可读存储介质用于存储至少一段程序代码，该至少一段程序代码由处理器加载并执行，以使得图像采集设备实现上述第二方面或第二方面中任一种可选方式所提供的图像采集方法。
第六方面，提供了一种计算机程序产品或计算机程序，该计算机程序产品或计算机程序包括程序代码，当其在图像采集设备上运行时，使得该图像采集设备执行上述第二方面或者第二方面的各种可选实现方式中提供的图像采集方法。
附图说明
图1是本申请实施例提供的一种图像采集系统的应用场景的示意图；
图2是本申请实施例提供的一种图像采集系统的架构示意图；
图3是本申请实施例提供的一种补光灯的架构示意图；
图4是本申请实施例提供的一种图像采集方法的流程图；
图5是本申请实施例提供的一种人眼相对视敏度的示意图；
图6是本申请实施例提供的一种图像传感器的QE曲线图；
图7是本申请实施例提供的一种第一可见光的示意图；
图8是本申请实施例提供的一种第二可见光的示意图；
图9是本申请实施例提供的一种白平衡处理方式的示意图；
图10是本申请实施例提供的一种图像采集装置的结构示意图；
图11是本申请实施例提供的一种图像采集设备的结构示意图。
具体实施方式
为使本申请的目的、技术方案和优点更加清楚，下面将结合附图对本申请实施方式作进一步地详细描述。
以下示例性介绍本申请的应用场景。
本申请实施例提供的图像采集系统能够应用在交通管理、社区安全管理以及事件检测等需要进行图像采集的场景中。具体而言，本申请实施例的图像采集系统和方法能够应用的场景包括但不限于：
场景一：卡口场景
图1是本申请实施例提供的一种图像采集系统的应用场景的示意图。如图1所示，为了实时监控交通路况和道路中通过的车辆，通常会在道路上设置卡口装置，实现对通过当前道路的所有车辆的实时监控，在该卡口装置上安装有包括摄像设备和补光灯的图像采集系统，摄像设备包括镜头和图像传感器，当有车辆进入当前卡口装置的监控范围时，由补光灯对当前道路环境进行补光，同时，由摄像设备对当前道路环境进行图像采集，以得到包含有当前通过卡口装置的车辆的图像。在该卡口场景中，采用本申请实施例提供的图像采集系统进行图像采集时，补光灯能够以人眼相对不敏感的可见光进行补光，极大地降低了光污染，且不会影响驾乘人员的视力，在图像采集的同时保证了交通安全。
场景二：社区出入管理场景
在社区安全管理的过程中，为了提高社区的安全性，通常会在社区的出入口设置视频监控装置对出入社区的车辆、人员进行实时监控，在该视频监控装置上安装有包括摄像设备和补光灯的图像采集系统，摄像设备包括镜头和图像传感器，当有车辆或人员通过社区的出入口时，由补光灯对当前社区环境进行补光，由摄像设备对车辆或人员进行图像采集，便于统计出入社区的车辆和人员。在该社区出入管理场景中，采用本申请实施例提供的图像采集系统进行图像采集时，补光灯能够以人眼相对不敏感的可见光进行补光，极大地降低了光污染，且不会影响出入社区的人员或者车辆内驾乘人员的视力。
需要说明的是，上述场景仅为示例性的描述，本申请实施例提供的图像采集系统能够应用于多种需要进行图像采集的场景，本申请实施例对于图像采集系统的应用场景不作限定。
为了更方便理解，下面对本申请实施例中涉及到的技术用语进行说明。
光谱(spectrum)是复色光经过色散系统(如棱镜、光栅)分光后，被色散开的单色光按波长(或频率)大小而依次排列的图案，全称为光学频谱。光谱中最大的一部分可见光谱是电磁波谱中人眼可见的一部分，在这个波长范围内的电磁辐射被称作可见光。人眼所感知的不同波长范围的光可能具有不同的颜色，例如，490nm(纳米)至580nm波长范围的光为绿色光，620nm至600nm波长范围的光为橙色光，等等。但光谱并没有包含人类大脑视觉所能区别的所有颜色，譬如褐色和粉红色。
特殊光谱是指一种相比于环境光光谱和一般光谱存在区别的光谱，其区别在于，这种特殊光谱的波长范围、各波长能量比例与环境光光谱以及一般光谱明显不一样，具体的光谱范围和能量比例选取是基于提高图像传感器的补光效率，也就是提供相同照度的补光情况下，极大的降低人眼炫目指数。
视敏特性是指人眼对不同波长的光具有不同灵敏度的特性，即人眼对辐射功率相同的各色光具有不同的亮度感觉。
图像信号处理(image signal process，ISP)是对图像传感器输出的信号进行处理，主要包括自动曝光控制(automatic exposure control，AEC)、自动增益控制(automatic gain control，AGC)、自动白平衡、色彩校正、镜头阴影校正、祛除坏点、降噪、锐化等等。
在本申请实施例中涉及的图像传感器包括感光耦合器件(charge-coupled device,CCD)图像传感器。还包括基于互补金属氧化物半导体(complementary metal oxide semiconductor，CMOS)工艺得到的图像传感器，这种图像传感器也称为CMOS图像传感器(CMOS image sensor)，是网络摄像机、数码相机和其他电子光学设备的核心部件。当然，在一些实施例中还可能包括其他类型的图像传感器，在此，本申请实施例对所涉及到的图像传感器的类型不做具有限定。
图像融合(image fusion)是一种图像处理技术，使用特定的算法将两幅或多幅图像综合成一幅新的图像，合成后的图像具备原始图像的优良特性，例如亮度、清晰度、色彩等。常见的图像融合技术有可见光图像与红外图像的融合。
量子效率(quantum efficiency，QE)是直接影响图像传感器光电性能的因素，因为光电转换效率的任何损耗都会直接减低信噪比(signal-to-noise ratio，SNR)。它的影响是两方面的，因为当散粒噪声(信号的平方根)是主要噪声源时，QE不单是信噪比的被除数(信号)，同时也是除数(噪声)。在这一点之上，CCD图像传感器和CMOS图像传感器处于同一水平，可是CCD图像传感器在QE改进方面累积有多年的技术工艺优化，而在CMOS图像传感器的QE改进发展相对较迟。
RAW图像格式(RAW image format)是CMOS图像传感器或者CCD图像感应器将捕捉到的光源信号转化为数字信号的原始数据。RAW文件是一种记录了数码相机传感器的原始信息，同时记录了由相机拍摄所产生的一些元数据(如快门速度、光圈值、白平衡等)的文件。RAW是未经处理、也未经压缩的格式，可以把RAW概念化为“原始图像编码数据”或更形象的称为“数字底片”。RAW图像格式的类型包括：RGGB，RYYB，RCCC、RCCB、RGBW以及CMYW等。
红绿蓝(redgreenblue，RGB)色彩模式是工业界的一种颜色标准，是通过对红R、绿G、蓝B三个颜色通道的变化以及它们相互之间的叠加来得到各式各样的颜色的，RGB即是代表红、绿、蓝三个通道的颜色，这个标准几乎包括了人类视力所能感知的所有颜色，是目前运用最广的颜色系统之一。使用ISP可以把各种格式的RAW图像转换成RGB格式。
光强是指发光强度(luminous intensity)，在光度学中简称光强或光度。用于表示光源给定方向上单位立体角内光通量的物理量，国际单位为坎德拉，符号：cd，也称烛光、支光。
光照强度是一种物理术语，指单位面积上所接受可见光的光通量。简称照度，单位为勒克斯(lux或lx)，用于指示光照的强弱和物体表面积被照明程度的量。
相对强度是指不同波长所对应的光强占总光强的能量比例。
下面对本申请实施例提供的图像采集系统的架构进行介绍。
图2是本申请实施例提供的一种图像采集系统的架构示意图。该图像采集系统包括：镜头201、图像传感器202、补光灯203以及图像处理单元204。
镜头201，用于采集目标区域的光线；
图像传感器202，用于对镜头201采集的光线进行光电转换以生成原始图像，并将该原始图像发送至图像处理单元204；
补光灯203，用于在低照度环境下，以第一可见光进行补光，该第一可见光的波长范围属于380nm(纳米)至680nm的波长范围，该第一可见光中人眼不敏感的波长光所对应的光强高于该第一可见光中人眼敏感的波长光所对应的光强；
图像处理单元204，用于在接收到该原始图像后，对该原始图像进行白平衡处理。
可选地，该第一可见光的波长范围为400nm至650nm。
可选地，该人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm；该人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm。
可选地，该人眼不敏感的波长光是指不包括绿光的波长光；该人眼敏感的波长光是指包括绿光的波长光。
可选地，该图像处理单元204，用于对该原始图像中各个通道的灰度值进行调整。
可选地，对原始图像中各个通道的灰度值进行调整是指对原始图像中至少一个通道的灰度值进行提升。
可选地，该图像处理单元204，用于：
基于该原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行直方图统计，得到该各个通道的最大灰度值和最小灰度值；
基于该最大灰度值和最小灰度值，对该各个通道的灰度值进行对比度线性拉升处理。
可选地，该图像处理单元204，用于：
基于该原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行统计，得到该各个通道的平均灰度值；
基于该平均灰度值，对该各个通道的灰度值进行增益处理。
可选地，该补光灯203，还用于在正常照度环境下，以第二可见光进行补光，该第二可见光的波长范围为380nm至680nm，该第二可见光中人眼不敏感的波长光所对应的光强低于该第二可见光中人眼敏感的波长光所对应的光强。
在该图像采集系统中，补光灯能够在目标区域处于低照度环境下时，以人眼相对不敏感的可见光进行补光，这样可以有效降低光污染，同时，基于这种补光方式，由图像处理单元对原始图像进行白平衡处理，使得最终输出的图像不会发生偏色。
下面对本申请实施例提供的图像采集系统中的补光灯203的架构进行介绍。
图3是本申请实施例提供的一种补光灯的架构示意图。如图3所示，该补光灯203包括：灯体2031、控制器2032、电机2033、光源2034以及滤光叶片2035，其中，控制器2032、电机2033和光源2034均位于灯体2031内部，控制器2032分别与电机2033和光源2034连接，滤光叶片2035位于灯体2031的开口处，由电机2033驱动实现开合操作，其中，开合操作是指由电机2033驱动滤光叶片2035打开或关闭。
控制器2032，用于控制光源2034发光，并控制电机2033工作；
电机2033，用于受到控制器2032控制，驱动滤光叶片2035关闭；
光源2034，用于受到控制器2032控制进行发光；
滤光叶片2035，用于在滤光叶片2035处于关闭状态下，对光源2034发出的光线进行过滤，以透过第一可见光，使得第一可见光向目标区域发射，实现对目标区域的补光。
需要说明的是，图3所示仅为本申请实施例提供的一种示例性的补光灯架构示意图，在实际应用中，上述各个组件的位置能够根据用户的需求进行设置，另外，补光灯的组件并不仅限于上述2031至2035，在实际应用中，能够根据用户的需求设置更多组件。本申请实施例对于补光灯的架构并不作限定。
以上介绍了本申请实施例提供的图像采集系统的系统架构，下面对本申请实施例提供的 图像采集方法进行示例性的说明。
图4是本申请实施例提供的一种图像采集方法的流程图，在本申请实施例中，该图像采集方法应用于上述图像采集系统。该图像采集系统包括：镜头、图像传感器、补光灯以及图像处理单元。该方法包括以下步骤：
401、控制单元确定需要对目标区域进行图像采集。
在一些实施例中，图像采集系统还包括控制单元，该控制单元能够用于确定需要对目标区域进行图像采集满足图像采集条件，也即是本步骤401由该控制单元来执行。目标区域是指需要进行图像采集的区域。可选地，该目标区域为距离镜头预设距离内的区域，例如，目标区域为距离镜头50m范围内的区域。本申请实施例对于目标区域的划定不作具体限定。
在一种可能的实现方式中，若该目标区域满足图像采集条件，则该控制单元确定需要对该目标区域进行图像采集。
可选地，图像采集条件包括目标区域中的目标对象处于目标位置，例如，目标对象为车辆，当车辆处于目标位置时，图像采集系统采集到的车辆图像的效果最佳，此时目标区域满足图像采集条件。可选地，图像采集条件包括目标区域中有活动对象，例如，该活动对象为行驶中的车辆、自行车等交通工具，再例如，该活动对象为发生动作变化的人，等等。可选地，该图像采集条件包括图像采集的时间满足时间要求，该时间要求包括当前时间为预先设置的图像采集时间，例如，每间隔10分钟，对目标区域进行图像采集，再例如，在检测到车辆后，对目标区域进行图像采集。在实际应用中，能够根据需求对图像采集条件进行设置，本申请实施例对此不作限定。
402、控制单元确定目标区域处于低照度环境。
其中，低照度环境为光照强度小于或等于预设阈值的环境，或处于目标时间段的环境，在一些实施例中，低照度环境也称为夜间环境。该目标时间段也即是处于夜间的时间段，例如0点至6点，18点至24点。
在本步骤402中，图像采集系统在确定目标区域处于低照度环境时，能够采用以下方式1或方式2中的任一种方式来实现：
方式1、图像采集系统获取目标区域内的光照强度，若光线照度小于或等于预设阈值，则图像采集系统确定该目标区域处于低照度环境。
例如，该图像采集系统设置预设阈值为15lux，当目标区域满足图像采集条件时，图像采集系统获取目标区域内当前的光照强度，若获取到的光照强度小于或等于15lux，则确定目标区域处于低照度环境，若获取到的光照强度大于15lux，则确定目标区域处于正常照度环境。需要说明的是，本申请实施例对于光照强度的预设阈值的设定以及判断方式不作具体限定。
方式2、图像采集系统获取当前时间，若所获取到的当前时间处于目标时间段内，则图像采集系统确定该目标区域处于低照度环境。
例如，该图像采集系统预先设置目标时间段为每天0点至6点，以及18点至24点，当目标区域满足图像采集条件时，图像采集系统获取当前时间，若获取到的当前时间为22点，则确定目标区域处于低照度环境，若获取到的当前时间为8点，则确定目标区域处于正常照度环境。需要说明的是，本申请实施例对于目标时间段的设定不作具体限定。
需要说明的是，上述两种确定目标区域是否处于低照度环境的方法仅为示意性的，在实 际应用中，能够根据实际需求选择其他确定方法，本申请实施例对此不作限定。在一种可能的实现方式中，本步骤402由图像采集系统中的控制单元来执行，当控制单元确定目标区域处于低照度环境后，由控制单元控制镜头执行下述步骤403。可选地，控制单元为控制器或传感器。
经过上述步骤402，图像采集系统确定目标区域处于低照度环境，则在该低照度环境下，对目标区域进行图像采集，执行下述步骤403至步骤407。
403、在该低照度环境下，控制单元控制镜头采集该目标区域的光线。
在该控制单元的控制下，该镜头采集该目标区域的光线，在此，本申请实施例对该控制单元控制该镜头采集该目标区域光线的方式不作具体限定。例如，控制单元通过该镜头的硬件接口控制镜头采集该目标区域的光线。
需要说明的是，上述步骤401和步骤402为本申请实施例提供的一种可选地实现方式，也即是通过控制单元确定需要对目标区域进行图像采集，然后确定目标区域处于低照度环境，再由控制单元控制镜头执行本步骤403。
404、补光灯以第一可见光进行补光，该第一可见光的波长范围属于380nm至680nm的波长范围，该第一可见光中人眼不敏感的波长光所对应的光强高于该第一可见光中人眼敏感的波长光所对应的光强。
在本申请实施例中，第一可见光是由补光灯中的滤光叶片对光源所发出的光进行过滤后且能够透过滤光叶片的光。其中，380nm至680nm可以表示为(380nm，680nm)，也可以表示为[380nm，680nm]，本申请实施例对此不作限定。
在第一可见光中，存在两种波长光，一种是人眼不敏感的波长光，另一种是人眼敏感的波长光，其中，人眼不敏感的波长光是指不包括绿光的波长光，人眼不敏感的波长光也可以理解为除绿光以外的光，在一些实施例中，人眼不敏感的波长光也可以包括少量的绿光，由于绿光能量进行了部分衰减，绿光在第一可见光中的相对比例降低了，从而人眼相对不敏感了。人眼敏感的波长光是指包括绿光的波长光，或者也可以说，人眼敏感的波长光为包括大量绿光的光，由于绿光量多，人眼敏感。
在一些实施例中，人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm，可以表示为(400nm，480nm)以及(620nm，650nm)，或者，也可以表示为[400nm，480nm]以及[620nm，650nm]；人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm，可以表示为[480nm，620nm]，或者，也可以表示为(480nm，620nm)。
在另一些实施例中，人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至450nm，以及600nm至650nm，可以表示为(400nm，450nm)以及(600nm，650nm)，或者，也可以表示为[400nm，450nm]以及[600nm，650nm]；人眼敏感的波长光所处的波长范围在以下波段之内：450nm至600nm，可以表示为[450nm，600nm]，或者，也可以表示为(450nm，600nm)。
需要说明的是，本申请实施例对于上述人眼不敏感的波长光和人眼敏感的波长光的波长范围不作限定，在实际应用中，能够根据用户的需求进行针对性的设置。
下面结合实验结果，对本步骤404中第一可见光的确定方式进行说明。
首先参考图5，图5是本申请实施例提供的一种人眼相对视敏度的示意图。如图5中左图所示，该图是根据正常视力的观察者实验统计的结果得到的曲线，分为明视觉和暗视觉两条视敏函数曲线。从明视觉视敏函数曲线可知，当波长位于555nm时，人眼的相对视敏度最 高，从暗视觉视敏函数曲线可知，当波长位于507nm时，人眼的相对视敏度最高，这两种视敏函数曲线最大值所对应的波长相差近50nm，这是因为人眼的视网膜上有两种光敏细胞，一种是杆状细胞，另一种是锥状细胞，在明、暗两种情况下，由这两种光敏细胞分别产生作用，导致在明、暗两种视觉条件下得到的视敏函数曲线有偏差，由此得出，人眼就相当于带通滤波器，对亮度的变化比较敏感。如图5中右图所示，人眼对于蓝光的视觉灵敏度要比红光和绿光低得多，其中，三条曲线的峰值比为R:G:B＝0.54:0.575:0.053(蓝光放大20倍)，三条曲线有相当一部分是重叠的，正常观察条件下，人眼得到的是三者的合成的视觉，不能将他们各自的数值区分开，大脑根据三者的比例，感知彩色的色调和饱和度，而三者的和决定了光的总亮度。从右图中也能得出，人眼对绿光的视觉灵敏度要比红光和蓝光都高，因此，人眼对绿光是更为敏感的。
接着参考图6，图6是本申请实施例提供的一种图像传感器的QE曲线，从图6中能够得出，红光所对应的相对强度要高于绿光和蓝光所对应的相对强度，图像传感器对相对强度越高的光越敏感，因此图像传感器对于红光的灵敏度要比蓝光和绿光高。
基于上述图5和图6的分析结果可知，人眼对绿光是更为敏感的，对蓝光和红光相对不敏感，而图像传感器对红光是更为敏感的，对绿光和蓝光相对不敏感，因此，在波长范围为380nm至680nm的可见光中，降低人眼敏感的波长光所对应的光强，也即是绿光所对应的光强，以得到第一可见光。同时，由于图像传感器对绿光的敏感度相对不高，因此，不会过度影响图像传感器对光线的转换功能。
在实际应用中，考虑到镜头实际采集的光线对应的波长光的波长范围为400nm至650nm，因此，在一些实施例中，第一可见光的波长光的波长范围为400nm至650nm。本申请实施例对于第一可见光的波长范围的具体选取方式不作限定。
下面对人眼不敏感的波长光以及人眼敏感的波长光的两种选取方式进行举例说明。
第一种选取方式、将波长在400nm至480nm，以及620nm至650nm之间的波长光作为人眼不敏感的波长光；将波长在480nm至620nm之间的波长光作为人眼敏感的波长光。
第二种选取方式、将波长在400nm至450nm，以及600nm至650nm之间的波长光作为人眼不敏感的波长光；将波长在450nm至600nm之间的波长光作为人眼敏感的波长光。
上述两种选取方式仅为本申请实施例提供的两种示例，在实际应用中，能够根据用户的需求选择合理的人眼不敏感的波长光以及人眼敏感的波长光，本申请实施例对此不作限定。
下面以上述第二种选取方式为例，对本步骤中的第一可见光进行具体说明。
参考图7和图8，其中，图7是本申请实施例提供的一种第一可见光的示意图；图8是本申请实施例提供的一种第二可见光的示意图，图8所示的第二可见光也即是本申请实施例提供的补光灯中光源所发出的光。
如图7所示，在波长范围为400nm至650nm的可见光内，可以划分为三段波长光，分别为400nm至450nm，450nm至600nm，以及600nm至650nm，且这三段波长光所对应的光强占总光强的能量比例为1.42:1.56:1。其中，450至600nm范围内的波长光即为人眼敏感的波长光，400nm至450nm，以及600nm至650nm波长范围内的波长光即为人眼不敏感的波长光。
如图8所示，在波长范围为400nm至650nm的可见光内，可以划分为三段波长光，分别为400至450nm，450至600nm，以及600至650nm，且这三段波长光所对应的光强占总光 强的能量比例为1.42:4.68:1。其中，450至600nm范围内的波长光即为人眼敏感的波长光，400nm至450nm，以及600nm至650nm波长范围内的波长光即为人眼不敏感的波长光。
结合图7和图8能够得出，图7中人眼敏感的波长光所对应的光强相比于图8中人眼敏感的波长光所对应的光强明显减弱，也即是在图8所示第二可见光的基础上，对人眼敏感的波长光的能量比例进行了下降调整，得到了如图7所示的第一可见光。
另外，需要说明的是，在一些实施例中，在对第二可见光中人眼敏感的波长光的能量比例进行下降调整后，第二可见光中人眼不敏感的波长光所对应的光强还是低于人眼敏感的波长光所对应的光强，但这种情况由于降低了第二可见光中人眼敏感的波长光的能量比例，也实现了降低光污染的效果。相应地，本步骤404中“该第一可见光中人眼不敏感的波长光所对应的光强高于该第一可见光中人眼敏感的波长光所对应的光强”能够替换为“该第一可见光中人眼敏感的波长光所对应的光强低于第二可见光中人眼敏感的波长光所对应的光强”。本申请实施例对此不作限定。
需要说明的是，图7所示仅为第一可见光的一种示例性的说明，在实际应用中，能够根据用户的需求灵活地对补光时各段波长光的能量比例进行调整，本申请实施例对此不作限定。
下面对本步骤404中补光灯的补光方式进行说明。
在本申请实施例中，补光灯包括：灯体、控制器、电机、光源以及滤光叶片，光源、电机以及控制器均位于灯体内部，控制器分别与电机和光源连接，滤光叶片位于灯体的开口处，由电机驱动实现开合操作。具体可参考图3理解补光灯的架构。补光灯的补光方式具体包括以下步骤一至步骤四：
步骤一：控制器控制光源发光，并控制电机工作。
步骤二：光源受到控制器控制进行发光。
步骤三：电机受到控制器控制，驱动滤光叶片关闭。
其中，滤光叶片的关闭方式为以下任意一种：第一种，电机能够驱动滤光叶片在灯体开口处以左右推动的方式关闭，具体可参考自动开合门的关闭方式。第二种，电机能够驱动滤光叶片在灯体开口以上下旋转或左右旋转的方式关闭，具体可参考百叶窗扇片的关闭方式。第三种，电机能够驱动滤光叶片在灯体开口处以顺时针旋转或逆时针旋转的方式关闭，具体可参考折扇的开扇方式。需要说明的是，在实际应用中，滤光叶片的关闭方式并不仅限于上述三种方式，而是能够以任意一种活动方式进行设置，具体地，根据用户的需求对滤光叶片的活动方式进行设置，例如，考虑成本需求、美观需求、使用寿命需求等，本申请实施例对于滤光叶片的活动方式不作具体限定。
步骤四：滤光叶片在处于关闭状态下，对光源发出的光线进行过滤，以透过第一可见光。
在步骤四中，滤光叶片处于关闭状态，遮挡了光源，使得光源所发出的可见光通过该灯体开口处向目标区域发射，实现对目标区域的补光。
其中，滤光叶片是基于第一可见光，在塑料或玻璃基材中重新加入特种染料或在基材表面镀光学膜得到的。滤光叶片处于关闭状态时，遮挡了补光灯中的光源，对于光源所发出的可见光，该滤光叶片能够对其进行过滤，使得透过滤光叶片的第一可见光中，人眼不敏感的波长光所对应的光强高于人眼敏感的波长光所对应的光强，实现补光灯以第一可见光进行补光。需要说明的是，本申请实施例对于滤光叶片的具体材质、制造方法以及形状参数等不作具体限制，在实际应用中，能够根据用户的需求制造滤光叶片。
需要说明的是，在实际应用中，滤光叶片在对光源所发出的可见光进行过滤时，存在一定误差，也即是，并不能够正好对某一数值范围内的可见光进行过滤，例如，该滤光叶片设置为对波长范围为450nm至600nm之间的可见光进行过滤，实际上，滤光叶片在过滤时可能会对440nm至610nm之间的可见光进行过滤。因此，应当知晓，任何与本申请实施例所提供的第一可见光类似或相近的可见光均在本申请实施例的保护范围之内。
另外，在本申请实施例中，在低照度环境下，能够通过提高补光灯中光源的功率，来增加光源所提供的第二可见光的光照强度。例如，将第二可见光的光照强度提升至100lux，即使第二可见光经过滤光叶片的过滤，补光灯向目标区域发出的第一可见光的光照强度也比较高，可以达到60lux，在这样较高的光照强度下，可以较好地对目标区域进行补光，以便镜头能够采集到更加清晰的图像，并且，人眼对第一可见光是不敏感的，因此即使补光灯以第一可见光对目标区域进行补光，也不会刺激到人眼，因此，该图像采集系统在达到理想补光效果的同时，也能够保护人眼。
需要说明的是，上述步骤403和步骤404是同步进行的，也即是，镜头在对目标区域进行光线采集的同时，由补光灯以第一可见光对目标区域进行补光。
405、图像传感器对镜头采集的光线进行光电转换以生成原始图像。
在本申请实施例中，原始图像是指在低照度环境下，图像传感器基于镜头采集的光线，直接生成的RAW图像。
406、图像传感器将该原始图像发送至图像处理单元。
407、图像处理单元在接收到该原始图像后，对该原始图像进行白平衡处理。
在本申请实施例中，白平衡处理是指对该原始图像中各个通道的灰度值进行调整，使原始图像中各个通道的灰度值达到均衡状态。其中，各个通道是指R通道、G通道以及B通道。
在本步骤中，白平衡处理包括下述任一种处理方式：
第一种处理方式、对原始图像进行对比度的线性拉升处理。包括以下步骤4071至步骤4073：
步骤4071、图像处理单元基于原始图像，获取原始图像中各个通道的灰度值。
步骤4072、图像处理单元对各个通道的灰度值进行直方图统计，得到各个通道的最大灰度值和最小灰度值。
其中，最大灰度值和最小灰度值是各个通道在统计阈值下的最大灰度值和最小灰度值。具体地，对于一个通道的直方图，图中灰度值按照从低到高的顺序，处于第一区间内的像素数所对应的总灰度值即为最小灰度值；图中灰度值按照从高到低的顺序，处于第二区间内的像素数所对应的总灰度值即为最大灰度值。可选地，第一区间和第二区间设置为百分比形式，例如，第一区间和第二区间均设置为前0.5％，也即是，对于一个通道的直方图，图中灰度值按照从低到高的顺序，将前0.5％的像素数所对应的灰度值进行累加，得到最小灰度值；图中灰度值按照从高到低的顺序，将前0.5％的像素数所对应的灰度值进行累加，得到最大灰度值。本申请实施例对于第一区间和第二区间的具体设置方式不作限定。
步骤4073、图像处理单元基于最大灰度值和最小灰度值，对各个通道的灰度值进行对比度的线性拉升处理。
为了进一步说明上述步骤4071至步骤4073的过程，下面以R通道为例，参考图9所示的本申请实施例提供的一种白平衡处理方式的示意图，对第一种白平衡处理方式进行具体说 明：
图像处理单元获取到原始图像中R通道的灰度值，对该R通道的灰度值做直方图统计，然后确定该直方图中的最低灰度值V min和最高灰度值V max，基于这两个灰度值，根据以下公式(1)对R通道的灰度值进行对比度的线性拉升处理。
V′＝CLIP(NMAX×(V-V min)/(V max-V min)，0，NMAX)  (1)
式中，V表示拉升前的灰度值，V′表示拉升后的灰度值，CLIP(x,min,max)函数表示将x限定到min到max之间，也即是，将NMAX×(V-V min)/(V max-V min)限定到0到NMAX之间，其中，NMAX表示数据域的理论最大值。
采用上述对R通道的对比度的线性拉升处理方式，对G通道和B通道进行相同处理，使三个通道的图像数据达到均衡状态。
第二种处理方式、对原始图像进行增益处理。具体包括以下步骤407A至步骤407C：
步骤407A、图像处理单元基于第一抓拍图像，获取第一抓拍图像中各个通道的灰度值。
步骤407B、图像处理单元对各个通道的灰度值进行统计，得到各个通道的平均灰度值。
其中，图像处理单元对各个通道的灰度值分别进行求和，然后计算得到各个通道的平均灰度值分别为：
Figure PCTCN2020138043-appb-000001
和
Figure PCTCN2020138043-appb-000002
步骤407C：图像处理单元基于各个通道的平均灰度值，对各个通道的灰度值进行增益处理。
其中，图像处理单元基于从上述步骤407B中得到的各个通道的平均灰度值，根据以下公式(2)至公式(4)，分别对各个通道的灰度值进行增益处理。公式(2)至公式(4)为：
Figure PCTCN2020138043-appb-000003
Figure PCTCN2020138043-appb-000004
Figure PCTCN2020138043-appb-000005
上述公式(2)至(4)中，
Figure PCTCN2020138043-appb-000006
表示
Figure PCTCN2020138043-appb-000007
中的最大值。
上述第二种处理方式中，
Figure PCTCN2020138043-appb-000008
表示
Figure PCTCN2020138043-appb-000009
中的最大值，其分别除以
Figure PCTCN2020138043-appb-000010
得到的是大于或等于1的数值，因此，上述对原始图像进行增益处理也即是对至少一个通道的灰度值进行提升。例如，当
Figure PCTCN2020138043-appb-000011
为
Figure PCTCN2020138043-appb-000012
中的最大值时，
Figure PCTCN2020138043-appb-000013
除以
Figure PCTCN2020138043-appb-000014
得到的数值为1，
Figure PCTCN2020138043-appb-000015
分别除以G和B得到是大于1的数值，则上述增益处理的过程即是对G通道和B通道的灰度值进行提升的过程。
需要说明的是，在实际应用中，用户能够根据需求对原始图像进行白平衡处理，并不仅限于上述两种白平衡处理方式，本申请实施例对此不作限定。
通过步骤407，由图像处理单元对原始图像进行白平衡处理，使得原始图像中各个通道的灰度值达到均衡状态，由此输出得到的图像不会发生偏色，提高了图像质量。
需要说明的是，通过上述步骤401至步骤407，实现了在夜间环境下对目标区域进行图像采集时，以人眼相对不敏感的第一可见光对目标区域进行补光，然后对得到的原始图像进行白平衡处理，以得到不会发生偏色的高质量全彩图像，大大降低了夜间图像采集时由补光灯补光时产生的光污染。
408、控制单元确定目标区域处于正常照度环境。
在本申请实施例中，正常照度环境为光照强度大于预设阈值的环境，或不处于目标时间段的环境，在一些实施例中，正常照度环境也称为白天环境。
在一种可能的实现方式中，图像采集系统获取目标区域内的光照强度，若光照强度大于预设阈值，则图像采集系统确定目标区域处于正常照度环境。
在一种可能的实现方式中，图像采集系统获取当前时间，若所获取到的当前时间不处于目标时间段内，此时目标区域处于正常照度环境下。
在一些实施例中，本步骤408由图像采集系统中的控制单元来执行，当控制单元确定目标区域处于正常照度环境后，控制单元控制镜头执行下述步骤409。可选地，控制单元为控制器或传感器。
当图像采集系统确定目标区域处于正常照度环境时，则在该正常照度环境下，对目标区域进行图像采集，执行下述步骤409至步骤413。
409、在正常照度环境下，控制单元控制镜头采集该目标区域的光线。
其中，控制单元控制镜头采集该目标区域的光线的方式，在上述步骤403中已有相关介绍，在此不再赘述。
410、补光灯以第二可见光进行补光，该第二可见光的波长范围为380nm至680nm，该第二可见光中人眼不敏感的波长光所对应的光强低于该第二可见光中人眼敏感的波长光所对应的光强。
在本申请实施例中，第二可见光是由补光灯中光源所发出的光，该第二可见光的波长范围可以表示为(380nm，680nm)，也可以表示为[380nm，680nm]，本申请实施例对此不作限定。
本步骤中人眼不敏感的波长光以及人眼敏感的波长光的两种选取方式与上述步骤404中类似，故在此不再赘述。
下面以上述步骤404中所示的第二种选取方式为例，对本步骤410中的第二可见光进行具体说明。
例如，在图8中，450至600nm范围内的波长光即为人眼敏感的波长光，400nm至450nm，以及600nm至650nm波长范围内的波长光即为人眼不敏感的波长光。
下面对本步骤中补光灯的补光方式进行说明。
在本申请实施例中，补光灯的补光方式具体包括以下步骤一至步骤四：
步骤一：控制器控制光源发光，并控制电机工作。
步骤二：光源受到控制器控制进行发光。
步骤三：电机受到控制器控制，驱动滤光叶片打开。
其中，滤光叶片的打开方式为以下任意一种：第一种，电机能够驱动滤光叶片在灯体开口处以左右推动的方式打开，具体可参考自动开合门的打开方式。第二种，电机能够驱动滤光叶片在灯体开口以上下旋转或左右旋转的方式打开，具体可参考百叶窗扇片的打开方式。第三种，电机能够驱动滤光叶片在灯体开口处以顺时针旋转或逆时针旋转的方式打开，具体可参考折扇的闭扇方式。需要说明的是，在实际应用中，滤光叶片的打开方式并不仅限于上述三种方式，而是能够以任意一种活动方式进行设置，具体地，根据用户的需求对滤光叶片的活动方式进行设置，例如，考虑成本需求、美观需求、使用寿命需求等，本申请实施例对于滤光叶片的活动方式不作具体限定。
步骤四：滤光叶片在处于打开状态下，光源不受遮挡，光源发出的第二可见光通过灯体开口处向目标区域发射，以实现对目标区域的补光。
在本申请实施例中，补光灯在正常照度环境下，也即是白天环境下，提供高强度的补光， 并以第二可见光进行补光，例如，光照强度为20000lux。
需要说明的是，上述步骤409和步骤410是同步进行的，也即是，镜头在对目标区域进行光线采集的同时，由补光灯以第二可见光对目标区域进行补光。
411、图像传感器对镜头采集的光线进行光电转换以生成原始图像。
412、图像传感器将该原始图像发送至图像处理单元。
413、图像处理单元在接收到该原始图像后，对该原始图像进行常规图像处理。
在本申请实施例中，常规图像处理是指对原始图像按照默认的图像处理方式进行图像处理。本申请实施例对于图像处理的方式不作具体限定。
需要说明的是，通过上述步骤408至步骤413，实现了在白天环境下对目标区域进行图像采集时，以第二可见光对目标区域进行补光，然后对得到的原始图像进行常规图像处理，以得到不会发生偏色的高质量全彩图像。
上述步骤401至步骤413通过控制补光灯中滤光叶片的打开和关闭，实现在白天环境和夜间环境下都只需通过这一个补光灯进行补光，不会造成额外的光污染，也大大节约了成本。
在本申请实施例提供的图像采集方法中，当目标区域处于低照度环境下时，由补光灯以第一可见光进行补光，这种第一可见光通过补光灯中的滤光叶片对光源发出的光进行过滤得到，是一种人眼相对不敏感的可见光，因此可以有效降低光污染，同时，基于这种补光方式，由图像处理单元对原始图像进行白平衡处理，使得最终输出的图像不会发生偏色；当目标区域处于正常照度环境下时，由补光灯以第二可见光进行补光，这种第二可见光是补光灯的光源直接发出的光，能够提供高强度的补光，通过上述方法，实现了仅用一个补光灯在白天环境和夜间环境进行针对性的补光，既降低了光污染，也节约了成本。
图10是本申请实施例提供的一种图像采集装置的结构示意图，该图像采集装置用于执行上述图像采集方法执行时的步骤，参见图10，该图像采集装置1000包括：采集模块1001、转换模块1002、补光模块1003以及图像处理模块1004；
采集模块1001，用于采集目标区域的光线；
转换模块1002，用于对该采集模块采集的光线进行光电转换以生成原始图像，并将该原始图像发送至该图像处理模块；
补光模块1003，用于在低照度环境下，以第一可见光进行补光，该第一可见光的波长范围属于380nm至680nm的波长范围，该第一可见光中人眼不敏感的波长光所对应的光强高于该第一可见光中人眼敏感的波长光所对应的光强；
图像处理模块1004，用于在接收到该原始图像后，对该原始图像进行白平衡处理。
可选地，该第一可见光的波长范围为400nm至650nm。
可选地，该人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm；该人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm。
可选地，该人眼不敏感的波长光是指不包括绿光的波长光；该人眼敏感的波长光是指包括绿光的波长光。
可选地，该图像处理模块1004用于对原始图像中各个通道的灰度值进行调整。
可选地，对原始图像中各个通道的灰度值进行调整是指对原始图像中至少一个通道的灰度值进行提升。
可选地，该图像处理模块1004用于：
基于原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行直方图统计，得到该各个通道的最大灰度值和最小灰度值；
基于该最大灰度值和最小灰度值，对该各个通道的灰度值进行对比度线性拉升处理。
可选地，该图像处理模块1004用于：
基于该原始图像，获取该原始图像中各个通道的灰度值；
对该各个通道的灰度值进行统计，得到该各个通道的平均灰度值；
基于该平均灰度值，对该各个通道的灰度值进行增益处理。
可选地，该补光模块1003包括：灯体、控制器、电机、光源以及滤光叶片，该光源、电机以及该控制器均位于该灯体内部，该控制器分别与该电机和该光源连接，该滤光叶片位于该灯体的开口处，由该电机驱动实现开合操作；该控制器控制该光源发光，并控制该电机工作；该光源受到该控制器控制进行发光；该电机受到该控制器控制，驱动该滤光叶片关闭；该滤光叶片在该滤光叶片处于关闭状态下，对该光源发出的光线进行过滤，以透过该第一可见光。
可选地，该补光模块1003还用于在正常照度环境下，以第二可见光进行补光，该第二可见光的波长范围为380nm至680nm，该第二可见光中人眼不敏感的波长光所对应的光强低于该第二可见光中人眼敏感的波长光所对应的光强。
在该图像采集装置中，补光模块能够在目标区域处于低照度环境下时，以人眼相对不敏感的可见光进行补光，这样可以有效降低光污染，同时，基于这种补光方式，由图像处理模块对原始图像进行白平衡处理，使得最终输出的图像不会发生偏色。
图11是本申请实施例提供的一种图像采集设备的结构示意图，该图像采集设备1100可因配置或性能不同而产生比较大的差异，包括一个或一个以上的处理器1101和一个或一个以上的存储器1102，其中，该存储器1102中存储有至少一条程序代码，该至少一条程序代码由该处理器1101加载并执行以实现上述方法实施例中图像采集系统所执行的操作。当然，该图像采集设备1100还能够具有有线或无线网络接口、键盘以及输入输出接口等部件，以便进行输入输出，该图像采集设备1100还包括其他用于实现设备功能的部件，在此不做赘述。
在示例性实施例中，还提供了一种计算机可读存储介质，例如包括程序代码的存储器，上述程序代码可由终端中的处理器执行以完成上述实施例中的图像采集方法。例如，该计算机可读存储介质是只读存储器(read-only memory，ROM)、随机存取存储器(random access memory，RAM)、只读光盘(compact disc read-only memory，CD-ROM)、磁带、软盘和光数据存储设备等。
本申请中术语“第一”“第二”等字样用于对作用和功能基本相同的相同项或相似项进行区分，应理解，“第一”、“第二”、“第n”之间不具有逻辑或时序上的依赖关系，也不对数量和执行顺序进行限定。还应理解，尽管以下描述使用术语第一、第二等来描述各种元素，但这些元素不应受术语的限制。这些术语只是用于将一元素与另一元素区别分开。例如，在不脱离各种所述示例的范围的情况下，第一图像可以被称为第二图像，并且类似地，第二图像可以被称为第一图像。第一图像和第二图像都可以是图像，并且在某些情况下，可以是单独且不同的图像。
本申请中术语“至少一个”的含义是指一个或多个，本申请中术语“多个”的含义是指两个或两个以上，例如，多个通道是指两个或两个以上的通道。本文中术语“系统”和“网络”经常 可互换使用。
还应理解，术语“如果”可被解释为意指“当...时”(“when”或“upon”)或“响应于确定”或“响应于检测到”。类似地，根据上下文，短语“如果确定...”或“如果检测到[所陈述的条件或事件]”可被解释为意指“在确定...时”或“响应于确定...”或“在检测到[所陈述的条件或事件]时”或“响应于检测到[所陈述的条件或事件]”。
以上描述，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到各种等效的修改或替换，这些修改或替换都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应以权利要求的保护范围为准。
以上所述，以上实施例仅用以说明本申请的技术方案，而非对其限制；尽管参照前述实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的范围。

Claims (23)

  1. 一种图像采集系统，其特征在于，所述系统包括：镜头、图像传感器、补光灯以及图像处理单元；
    所述镜头，用于采集目标区域的光线；
    所述图像传感器，用于对所述镜头采集的光线进行光电转换以生成原始图像，并将所述原始图像发送至所述图像处理单元；
    所述补光灯，用于在低照度环境下，以第一可见光进行补光，所述第一可见光的波长范围属于380nm至680nm的波长范围，所述第一可见光中人眼不敏感的波长光所对应的光强高于所述第一可见光中人眼敏感的波长光所对应的光强；
    所述图像处理单元，用于在接收到所述原始图像后，对所述原始图像进行白平衡处理。
  2. 根据权利要求1所述的系统，其特征在于，所述第一可见光的波长范围为400nm至650nm。
  3. 根据权利要求1至2任一项所述的系统，其特征在于，所述人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm；所述人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm。
  4. 根据权利要求1至3任一项所述的系统，其特征在于：
    所述人眼不敏感的波长光是指不包括绿光的波长光；
    所述人眼敏感的波长光是指包括绿光的波长光。
  5. 根据权利要求1至4任一项所述的系统，其特征在于，所述对所述原始图像进行白平衡处理是指对所述原始图像中各个通道的灰度值进行调整。
  6. 根据权利要求1至5任一项所述的系统，其特征在于，所述对所述原始图像中各个通道的灰度值进行调整是指对所述原始图像中至少一个通道的灰度值进行提升。
  7. 根据权利要求1至5任一项所述的系统，其特征在于，所述图像处理单元用于：
    基于所述原始图像，获取所述原始图像中各个通道的灰度值；
    对所述各个通道的灰度值进行直方图统计，得到所述各个通道的最大灰度值和最小灰度值；
    基于所述最大灰度值和最小灰度值，对所述各个通道的灰度值进行对比度线性拉升处理。
  8. 根据权利要求1至6任一项所述的系统，其特征在于，所述图像处理单元用于：
    基于所述原始图像，获取所述原始图像中各个通道的灰度值；
    对所述各个通道的灰度值进行统计，得到所述各个通道的平均灰度值；
    基于所述平均灰度值，对所述各个通道的灰度值进行增益处理。
  9. 根据权利要求1至8任一项所述的系统，其特征在于，所述补光灯包括：灯体、控制器、电机、光源以及滤光叶片，所述光源、所述电机以及所述控制器均位于所述灯体内部，所述控制器分别与所述电机和所述光源连接，所述滤光叶片位于所述灯体的开口处，由所述电机驱动实现开合操作；
    所述控制器用于控制所述光源发光，并控制所述电机工作；
    所述光源用于受到所述控制器控制进行发光；
    所述电机用于受到所述控制器控制，驱动所述滤光叶片关闭；
    所述滤光叶片用于在所述滤光叶片处于关闭状态下，对所述光源发出的光线进行过滤，以透过所述第一可见光。
  10. 根据权利要求1至9任一项所述的系统，其特征在于，所述补光灯，还用于在正常照度环境下，以第二可见光进行补光，所述第二可见光的波长范围为380nm至680nm，所述第二可见光中人眼不敏感的波长光所对应的光强低于所述第二可见光中人眼敏感的波长光所对应的光强。
  11. 一种图像采集方法，其特征在于，所述方法应用于图像采集系统，所述系统包括：镜头、图像传感器、补光灯以及图像处理单元，所述方法包括：
    所述镜头采集目标区域的光线；
    所述图像传感器对所述镜头采集的光线进行光电转换以生成原始图像，并将所述原始图像发送至所述图像处理单元；
    所述补光灯在低照度环境下，以第一可见光进行补光，所述第一可见光的波长范围属于380nm至680nm的波长范围，所述第一可见光中人眼不敏感的波长光所对应的光强高于所述第一可见光中人眼敏感的波长光所对应的光强；
    所述图像处理单元在接收到所述原始图像后，对所述原始图像进行白平衡处理。
  12. 根据权利要求11所述的方法，其特征在于，所述第一可见光的波长范围为400nm至650nm。
  13. 根据权利要求11至12任一项所述的方法，其特征在于，所述人眼不敏感的波长光所处的波长范围在以下波段之内：400nm至480nm，以及620nm至650nm；所述人眼敏感的波长光所处的波长范围在以下波段之内：480nm至620nm。
  14. 根据权利要求11至13任一项所述的方法，其特征在于：
    所述人眼不敏感的波长光是指不包括绿光的波长光；
    所述人眼敏感的波长光是指包括绿光的波长光。
  15. 根据权利要求11至14任一项所述的方法，其特征在于，所述对所述原始图像进行 白平衡处理，包括：对所述原始图像中各个通道的灰度值进行调整。
  16. 根据权利要求11至15任一项所述的方法，其特征在于，所述对所述原始图像中各个通道的灰度值进行调整是指对所述原始图像中至少一个通道的灰度值进行提升。
  17. 根据权利要求11至15任一项所述的方法，其特征在于，所述对所述原始图像进行白平衡处理，包括：
    基于所述原始图像，获取所述原始图像中各个通道的灰度值；
    对所述各个通道的灰度值进行直方图统计，得到所述各个通道的最大灰度值和最小灰度值；
    基于所述最大灰度值和最小灰度值，对所述各个通道的灰度值进行对比度线性拉升处理。
  18. 根据权利要求11至16任一项所述的方法，其特征在于，所述对所述原始图像进行白平衡处理，包括：
    基于所述原始图像，获取所述原始图像中各个通道的灰度值；
    对所述各个通道的灰度值进行统计，得到所述各个通道的平均灰度值；
    基于所述平均灰度值，对所述各个通道的灰度值进行增益处理。
  19. 根据权利要求11至18任一项所述的方法，其特征在于，所述补光灯包括：灯体、控制器、电机、光源以及滤光叶片，所述光源、所述电机以及所述控制器均位于所述灯体内部，所述控制器分别与所述电机和所述光源连接，所述滤光叶片位于所述灯体的开口处，由所述电机驱动实现开合操作，所述补光灯在低照度环境下，以第一可见光进行补光，包括：
    所述控制器控制所述光源发光，并控制所述电机工作；
    所述光源受到所述控制器控制进行发光；
    所述电机受到所述控制器控制，驱动所述滤光叶片关闭；
    所述滤光叶片在所述滤光叶片处于关闭状态下，对所述光源发出的光线进行过滤，以透过所述第一可见光。
  20. 根据权利要求11至19任一项所述的方法，其特征在于，所述方法还包括：
    所述补光灯在正常照度环境下，以第二可见光进行补光，所述第二可见光的波长范围为380nm至680nm，所述第二可见光中人眼不敏感的波长光所对应的光强低于所述第二可见光中人眼敏感的波长光所对应的光强。
  21. 一种图像采集装置，其特征在于，所述装置包括：采集模块、转换模块、补光模块以及图像处理模块；
    所述采集模块，用于采集目标区域的光线；
    所述转换模块，用于对所述采集模块采集的光线进行光电转换以生成原始图像，并将所述原始图像发送至所述图像处理模块；
    所述补光模块，用于在低照度环境下，以第一可见光进行补光，所述第一可见光的波长 范围属于380nm至680nm的波长范围，所述第一可见光中人眼不敏感的波长光所对应的光强高于所述第一可见光中人眼敏感的波长光所对应的光强；
    所述图像处理模块，用于在接收到所述原始图像后，对所述原始图像进行白平衡处理。
  22. 一种图像采集设备，其特征在于，所述图像采集设备包括处理器和存储器，所述存储器用于存储至少一段程序代码，所述至少一段程序代码由所述处理器加载并执行如权利要求11至20任一项所述的图像采集方法。
  23. 一种计算机可读存储介质，其特征在于，所述计算机可读存储介质用于存储至少一段程序代码，所述至少一段程序代码用于执行如权利要求11至权利要求20中任一项所述的图像采集方法。
PCT/CN2020/138043 2020-09-10 2020-12-21 图像采集系统、方法、设备及存储介质 WO2022052365A1 (zh)

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