TWI767468B - Dual sensor imaging system and imaging method thereof - Google Patents

Abstract

A dual sensor imaging system and an imaging method thereof are provided. The method includes following steps: identifying an imaging scene; controlling a color sensor and an IR sensor to respectively capture multiple color images and multiple IR images using multiple capturing conditions under the imaging scene; calculating a signal-to-noise ratio (SNR) difference between each color image and the IR images and a luminance mean value of each color image; selecting the color image and the IR image captured under the capturing condition having the SNR difference lower than or equal to a SNR threshold and having the luminance mean value higher than or equal to a luminance threshold for performing a feature domain transformation, so as to extract partial details of the imaging scene; and fusing the selected color image and IR image to adjust the partial details of the color image with a guidance of the partial details of the IR image, so as to obtain a scene image with full details of the imaging scene.

Description

Dual-sensor camera system and camera method thereof

The present invention relates to a camera system and method, and more particularly, to a dual-sensor camera system and a camera method thereof.

The camera's exposure conditions (including aperture, shutter, and sensitivity) affect the quality of the images captured, so many cameras automatically adjust exposure conditions during image capture to obtain clear and bright images. However, in scenes with high contrast such as low light source or backlight, the result of camera adjustment of exposure conditions may result in excessive noise or overexposure in some areas, and the image quality in all areas cannot be balanced.

In this regard, the current technology adopts a new image sensor architecture, which utilizes the characteristics of high light sensitivity of infrared (IR) sensors to intersperse and configure IR pixels among the color pixels of the image sensor to assist brightness detection. Measurement. For example, FIG. 1 is a schematic diagram of conventionally using an image sensor to capture images. Referring to FIG. 1 , in addition to red (R), green (G), blue (B) and other color pixels, the conventional image sensor 10 is also interspersed with infrared (I) pixels. Thereby, the image sensor 10 can combine the color information 12 captured by the R, G, and B color pixels with the luminance information 14 captured by the I pixel to obtain an image 16 with moderate color and brightness.

However, in the above-mentioned single image sensor structure, the exposure conditions of each pixel in the image sensor are the same, so only the exposure conditions that are more suitable for color pixels or infrared pixels can be selected to capture images, and the result is still ineffective. The characteristics of the two pixels are used to improve the image quality of the captured image.

The present invention provides a dual-sensor camera system and a camera method thereof, which utilize independently configured color and infrared sensors to capture multiple images under different shooting conditions, and select colors with appropriate exposure and noise within an allowable range. And the infrared image is fused into the result image, which can increase the details of the captured image and improve the image quality.

The dual-sensor camera system of the present invention includes at least one color sensor, at least one infrared sensor, a storage device, and a processor coupled to the color sensor, the infrared light sensor, and the storage device. The processor is configured to load and execute a computer program stored in the storage device to: identify the camera scene of the dual-sensor camera system; control the color sensor and the infrared sensor to use multiple methods suitable for the camera scene Capture multiple color images and multiple infrared images under different shooting conditions, the shooting conditions include different combinations of exposure time and sensitivity; calculate the difference between the signal-to-noise ratio of each color image and the signal-to-noise ratio of the infrared image, respectively, and the average brightness of each color image; choose to use the color images and infrared images captured under the shooting conditions where the signal-to-noise ratio difference is less than a signal-to-noise ratio threshold value and the brightness average value is greater than a brightness threshold value to perform feature domain conversion, extracting some details of the shooting scene; and fusing the selected color image and the infrared image to adjust some details of the color image according to the guidance of the partial details of the infrared image to obtain a scene image with complete details of the shooting scene.

The imaging method of the dual-sensor imaging system of the present invention is suitable for a dual-sensor imaging system comprising at least one color sensor, at least one infrared sensor and a processor. The method includes the following steps: recognizing the shooting scene of the dual-sensor camera system; controlling the color sensor and the infrared sensor to capture a plurality of color images and a plurality of infrared images respectively using a plurality of shooting conditions suitable for the shooting scene image, the shooting conditions include different combinations of exposure time and sensitivity; calculate the difference between the signal-to-noise ratio of each color image and the signal-to-noise ratio of the infrared image, and the average brightness of each color image; choose to use the signal-to-noise ratio Perform feature domain conversion on color images and infrared images captured under shooting conditions where the ratio difference is less than a signal-to-noise ratio threshold and the average brightness is greater than a brightness threshold, so as to extract some details of the shooting scene; and fuse the selected colors The image and the infrared image are used to adjust part of the details of the color image according to the guidance of the part of the details of the infrared image, so as to obtain a scene image with complete details of the shooting scene.

Based on the above, the dual-sensor camera system and the camera method thereof of the present invention capture a plurality of images on the independently configured color sensor and infrared sensor using different shooting conditions suitable for the current shooting scene, and according to the The difference in signal-to-noise ratio and brightness of the captured image is selected, and the color and infrared images with proper exposure and noise within the allowable range are selected to fuse the resulting image, which can increase the details of the captured image and improve the image quality.

FIG. 2 is a schematic diagram of capturing an image using an image sensor according to an embodiment of the present invention. Referring to FIG. 2 , the image sensor 20 of the embodiment of the present invention adopts a dual-sensor structure in which a color sensor 22 and an infrared (IR) sensor 24 are independently configured, and the color sensor 22 and the infrared sensor are used. 24 have their respective characteristics, use multiple exposure conditions suitable for the current shooting scene to capture multiple images respectively, and select the color image 22a and infrared image 24a with appropriate exposure conditions from them, and use the infrared image 24a to complement the image fusion method. The lack of texture details in the color image 22a results in a scene image 26 with good color and texture details.

FIG. 3 is a block diagram of a dual-sensor camera system according to an embodiment of the present invention. Please refer to FIG. 3 , the dual-sensor camera system 30 of this embodiment can be configured in electronic devices such as mobile phones, tablet computers, notebook computers, navigation devices, driving recorders, digital cameras, digital cameras, etc., to provide a camera function . The dual-sensor camera system 30 includes at least one color sensor 32, at least one infrared sensor 34, a storage device 36 and a processor 38, and its functions are described as follows:

The color sensor 32 includes, for example, a Charge Coupled Device (CCD), a Complementary Metal-Oxide Semiconductor (CMOS) device, or other types of photosensitive devices, and can sense light intensity to generate a camera scene image. The color sensor 32 is, for example, a red-green-blue (RGB) image sensor, which includes red (R), green (G), and blue (B) color pixels for capturing red light and green light in the camera scene , blue light and other color information, and combine these color information to generate a color image of the camera scene.

The infrared sensor 34 includes, for example, a CCD, a CMOS element or other types of photosensitive elements, which can sense infrared light by adjusting the wavelength sensing range of the photosensitive element. The infrared sensor 34, for example, uses the above-mentioned photosensitive elements as pixels to capture infrared light information in the imaging scene, and synthesizes the infrared light information to generate an infrared image of the imaging scene.

The storage device 36 is, for example, any type of fixed or removable random access memory (Random Access Memory, RAM), read-only memory (Read-Only Memory, ROM), flash memory (Flash memory), hard drive A disk or similar element, or a combination of the foregoing, for storing computer programs executable by the processor 38 . In some embodiments, the storage device 36 may also store, for example, the color image captured by the color sensor 32 and the infrared image captured by the infrared sensor 34 .

The processor 38 is, for example, a central processing unit (CPU), or other programmable general-purpose or special-purpose microprocessors (Microprocessors), microcontrollers (Microcontrollers), and digital signal processors (Digital Signal Processors). Processor, DSP), programmable controller, application specific integrated circuit (Application Specific Integrated Circuits, ASIC), programmable logic device (Programmable Logic Device, PLD) or other similar devices or a combination of these devices, the present invention does not this limit. In this embodiment, the processor 38 can load a computer program from the storage device 36 to execute the imaging method of the dual-sensor imaging system of the embodiment of the present invention.

Based on the fact that in extreme camera scenes such as late night (or low light source), bright sun or backlight, many parts of the color image will lose detail due to being too dark or overexposed, and these parts (i.e. the defect areas described later) need to be properly filled, In order to better improve the image quality. In this regard, the embodiments of the present invention ensure that the captured image can reveal at least some details of the defective area by adaptively adjusting the exposure time and/or the sensitivity (ISO) of the color sensor. For the adjustment of exposure time and/or sensitivity, the embodiments of the present invention also use pre-defined signal-to-noise ratio thresholds and brightness thresholds as appropriate limits, so as to achieve a balance among image details, brightness and noise.

FIG. 4 is a flowchart of an imaging method of a dual-sensor imaging system according to an embodiment of the present invention. Please refer to FIG. 3 and FIG. 4 at the same time. The method of this embodiment is applicable to the above-mentioned dual-sensor camera system 30 . The following describes the detailed steps of the camera method of this embodiment in combination with various elements of the dual-sensor camera system 30 . .

In step S402 , the camera scene of the dual-sensor camera system 30 is identified by the processor 38 . In some embodiments, the processor 38 controls at least one of the color sensor 32 and the infrared sensor 34 to capture at least one standard image of the camera scene using standard exposure conditions, and uses these standard images to Identify the camera scene. The standard exposure conditions include, for example, parameters such as aperture, shutter, and sensitivity determined by using the existing light metering technology. , Chroma, white balance and other image parameters to identify the camera scene, including the location of the camera scene (indoor or outdoor), light source (high light source or low light source), contrast (high contrast or low contrast), The type (object or portrait) or state (dynamic or static) of the photographed object, etc. In other embodiments, the processor 38 may also use a positioning method to identify the camera scene or directly receive user operations to set the camera scene, which is not limited herein.

In step S404, the processor 38 controls the color sensor 32 and the infrared sensor 34 to capture a plurality of color images and a plurality of infrared images respectively using a plurality of shooting conditions suitable for the identified shooting scene. In some embodiments, the processor 38 identifies whether a defect area lacking texture details is included in the camera scene, for example, by determining whether the captured image includes a bright area or a dark area lacking texture details. When identifying a defective area, the processor 38 determines the exposure time and sensitivity of each shooting condition based on, for example, exposure time and sensitivity in standard exposure conditions, and aiming at increasing the texture details of the defective area. Wherein, for the case where the photographing scene includes a bright part area and a dark part area lacking texture details, the corresponding implementations will be described in detail with examples hereinafter.

In step S406, the processor 38 calculates the difference between the signal-to-noise ratio of each color image and the signal-to-noise ratio of the infrared image, and the average brightness of each color image, and uses them to compare with the preset signal-to-noise ratio threshold. Compare with the luminance threshold. The signal-to-noise ratio threshold value and the brightness threshold value are, for example, pre-acquired images for various scenes under different shooting conditions, and by analyzing the image parameters such as the signal-to-noise ratio, brightness, etc. The quality of the image meets the required constraints. This qualification can be used by the processor 38 as a basis for selecting the color image and the infrared image.

In step S408, the processor 38 selects and uses the color image and the corresponding infrared image with the signal-to-noise ratio difference less than the signal-to-noise ratio threshold value and the luminance average value greater than the luminance threshold value to perform feature domain conversion, so as to extract some details of the shooting scene . The processor 38 , for example, selects a color image with more details of the shooting scene from among the plurality of color images whose SNR difference is less than the SNR threshold and the average brightness is greater than the brightness threshold as the subsequent color image to be used with infrared rays. The image of the image fusion, thereby increasing the details of the fusion image. In addition, the processor 38, for example, performs feature domain conversion such as color space conversion or gradient conversion on the selected color image and infrared image, thereby extracting more details of the camera scene in the images (such as color details, texture details or edge details) as the basis for subsequent image fusion.

In step S410, the processor 38 fuses the selected color image and the infrared image to adjust some details of the color image according to the guidance of the partial details of the infrared image to obtain a scene image with complete details of the shooting scene. In some embodiments, when the processor 38 fuses the color image and the infrared image, for example, using the guidance of texture details and/or edge details of the infrared image to enhance the color details in the color image, and finally obtain a complete image with the camera scene. Scene images with color, texture, edge detail.

It should be noted that, in some embodiments, the dual-sensor camera system 30 may be additionally configured with an infrared projector (IR projector), and the processor 38 may control the infrared sensor 32 to capture infrared images at the same time. By controlling the infrared projector to project infrared light to the shooting scene, the texture details in the infrared image captured by the infrared sensor 32 are increased.

In addition, in some embodiments, the texture details of some defective areas in the color image may not be enhanced or complemented by the infrared image due to certain factors, such as the parallax between the color sensor 32 and the infrared sensor 34 . ) will cause the infrared sensor 34 to be blocked. In this case, the processor 38, for example, controls the color sensor 32 to capture multiple color images with multiple exposure times that are longer or shorter than the exposure time of the selected color image and perform high dynamic range (HDR) ) processing to generate a scene image with texture detail in defective areas.

In some embodiments, the processor 38 controls the color sensor 32 to use an exposure time shorter than the exposure time and an exposure time longer than the exposure time, for example, according to the exposure time of the selected color image. A color image with a shorter exposure time and a color image with a longer exposure time are captured, and HDR processing is performed in combination with the color image captured with the original exposure time. That is, an area with better color and texture details is selected from the three color images to make up for the lack of detail in other color images, so as to obtain an HDR image with good details in both highlights and shadows as the final output scene image.

In some embodiments, the processor 38 may, for example, perform noise reduction (NR) processing such as 2D spatial denoise (2D spatial denoise) on the HDR image, so as to reduce noise in the HDR image and improve the quality of the final output image. image quality.

In a late night or low light source scene, even if the image is captured with a longer exposure time and/or a higher sensitivity, trying to increase the color and texture details of the captured image will result in a corresponding increase in image noise. In this regard, in order to ensure that the quality of the captured image is within an acceptable range, the embodiment of the present invention adaptively sets a plurality of shooting conditions that increase the exposure time and/or the sensitivity to shoot the image, and calculates the captured image by calculating The difference in signal-to-noise ratio and brightness value between images, select images with proper exposure and noise within the allowable range for fusion, so as to obtain scene images that can take into account the details and quality of the images.

FIG. 5 is a flowchart of an imaging method of a dual-sensor imaging system according to an embodiment of the present invention. Please refer to FIG. 3 and FIG. 5 at the same time. The method of the present embodiment describes the imaging method of the dual-sensor camera system 30 in the middle of the night or the scene of low light source. The following describes the implementation with the components of the dual-sensor camera system 30 . The detailed steps of the imaging method of the example.

In step S502, at least one of the color sensor 32 and the infrared sensor 34 is controlled by the processor 38 to capture at least one standard image of the camera scene using standard exposure conditions, and use these standard images to identify the camera Scenes. The definition of the standard exposure conditions and the way of identifying the imaging scene are as described in the foregoing embodiments, and will not be repeated here.

In step S504, the processor 38 identifies at least one dark area in the standard image that lacks texture details, and based on the exposure time and sensitivity of the standard shooting conditions, increases at least one of the exposure time and the sensitivity to determine more exposure time and sensitivity for each shooting condition. Wherein, the increased exposure time is, for example, any value in the exposure value (Exposure Value, EV) between 0.1 and 3, and the increased sensitivity is, for example, any value between 50 and 1000, which is not set here. limit.

In step S506, the processor 38 controls the color sensor 32 and the infrared sensor 34 to capture a plurality of color images and a plurality of infrared images respectively using the plurality of shooting conditions determined above.

In step S508, the processor 38 calculates the difference between the signal-to-noise ratio of each color image and the signal-to-noise ratio of the infrared image, and the average brightness of each color image, and uses them to compare with the preset signal-to-noise ratio threshold. Compare with the luminance threshold.

In step S510, the processor 38 selects and uses the color image and the corresponding infrared image whose signal-to-noise ratio difference is smaller than the signal-to-noise ratio threshold value and the luminance average value is greater than the luminance threshold value to perform feature domain conversion, so as to extract part of the camera scene detail.

In step S512, the processor 38 fuses the selected color image and the infrared image to adjust part of the detail of the color image according to the guidance of the part of the detail of the infrared image to obtain a scene image with complete details of the shooting scene. The implementations of the above steps S506 to S512 are the same as or similar to the steps S404 to S410 of the foregoing embodiment, so the details are not repeated here.

With the above method, even in the dark night or in the scene of low light source, the dual-sensor camera system 30 can capture and select a color image and an infrared image with proper exposure and noise within the allowable range for fusion, so as to maximize the image quality. Maximize the details of the captured images and improve the image quality.

In backlit scenes or high-brightness scenes, the background will be brighter than the subject, or overall brighter, which will cause the color image captured by the color sensor to lose color and texture details due to overexposure. In order to allow the captured images to include more details, the embodiments of the present invention adaptively set a plurality of shooting conditions that reduce exposure time and/or sensitivity and use them to capture images, by calculating the signal-to-noise ratio between the captured images and brightness value difference, select images with proper exposure and noise within the allowable range for fusion, so as to obtain scene images that can take into account the details and quality of the images.

FIG. 6 is a flowchart of an imaging method of a dual-sensor imaging system according to an embodiment of the present invention. Please refer to FIG. 3 and FIG. 6 at the same time. The method of this embodiment describes the imaging method of the dual-sensor camera system 30 in a backlight or high-brightness scene. The following describes this embodiment with the components of the dual-sensor camera system 30 . The detailed steps of the camera method.

In step S602, at least one of the color sensor 32 and the infrared sensor 34 is controlled by the processor 38 to capture at least one standard image of the camera scene using standard exposure conditions, and use these standard images to identify the camera Scenes. The definition of the standard exposure conditions and the way of identifying the imaging scene are as described in the foregoing embodiments, and will not be repeated here.

In step S604, the processor 38 identifies at least one bright area in the standard image lacking texture details, and determines at least one of the exposure time and the sensitivity based on the exposure time and sensitivity of the standard shooting conditions to reduce at least one of the exposure time and sensitivity. Exposure time and sensitivity for multiple shooting conditions. Wherein, the reduced exposure time is, for example, any value in the exposure value (Exposure Value, EV) between 0.1 and 3, and the reduced sensitivity is, for example, any value between 50 and 1000, which is not set here. limit.

In step S606, the processor 38 controls the color sensor 32 and the infrared sensor 34 to capture a plurality of color images and a plurality of infrared images respectively using the plurality of shooting conditions determined above.

In step S608, the processor 38 calculates the difference between the signal-to-noise ratio of each color image and the signal-to-noise ratio of the infrared image, and the average brightness of each color image, and uses them to compare with the preset signal-to-noise ratio threshold. Compare with the luminance threshold.

In step S610, the processor 38 selects the color image and the corresponding infrared image with the difference of the signal-to-noise ratio less than the signal-to-noise ratio threshold value and the brightness average value greater than the brightness threshold value and the corresponding infrared image to perform feature domain conversion, so as to extract the part of the shooting scene detail.

In step S612, the processor 38 fuses the selected color image and the infrared image to adjust some details of the color image according to the guidance of the partial details of the infrared image to obtain a scene image with complete details of the shooting scene. The implementations of the above steps S606 to S612 are the same as or similar to the steps S404 to S410 of the foregoing embodiment, so the details are not repeated here.

With the above method, even in a backlit or high-brightness scene, the dual-sensor camera system 30 can capture and select a color image and an infrared image with proper exposure and noise within the allowable range for fusion, thereby maximizing the image quality. Maximize the details of the captured images and improve the image quality.

To sum up, the dual-sensor camera system and the camera method of the present invention capture a plurality of images respectively using a plurality of shooting conditions suitable for the current shooting scene by independently configuring the color sensor and the infrared sensor, And according to the difference in signal-to-noise ratio and brightness of the captured images, images with proper exposure and noise within the allowable range are selected for fusion. Wherein, using the guidance of the texture and edge details of the infrared image to properly adjust the color details of the color image, the dual-sensor camera system of the present invention can finally obtain a scene image with complete details of the camera scene.

10, 20: Image sensor 12: Color Information 14: Brightness information 16: Video 22: Color Sensor 22a: Color Image 24: Infrared sensor 24a: Infrared imagery 26: Scene image 30: Dual-sensor camera system 32: Color Sensor 34: Infrared sensor 36: Storage device 38: Processor R, G, B, I: Pixels S402~S410, S502~S512, S602~S612: Steps

FIG. 1 is a schematic diagram of conventionally using an image sensor to capture images. FIG. 2 is a schematic diagram of capturing an image using an image sensor according to an embodiment of the present invention. FIG. 3 is a block diagram of a dual-sensor camera system according to an embodiment of the present invention. FIG. 4 is a flowchart of an imaging method of a dual-sensor imaging system according to an embodiment of the present invention. FIG. 5 is a flowchart of an imaging method of a dual-sensor imaging system according to an embodiment of the present invention. FIG. 6 is a flowchart of an imaging method of a dual-sensor imaging system according to an embodiment of the present invention.

S402~S410: Steps

Claims (16)

A dual-sensor camera system comprising: at least one color sensor; at least one infrared sensor; storage devices to store computer programs; and A processor, coupled to the at least one color sensor, the at least one infrared light sensor, and the storage device, is configured to load and execute the computer program to: identifying a camera scene of the dual-sensor camera system; controlling the at least one color sensor and the at least one infrared sensor to capture a plurality of color images and a plurality of infrared images respectively using a plurality of shooting conditions suitable for the shooting scene, the shooting conditions include exposure Different combinations of time and sensitivity; calculating the difference between the signal-to-noise ratio of each of the color images and the signal-to-noise ratio of the infrared image, and the average brightness of each of the color images; Selecting and using the color image and the corresponding infrared image with the difference of the signal-to-noise ratio less than a signal-to-noise ratio threshold value and the brightness average value greater than a brightness threshold value to perform feature domain conversion to extract the image some details of the scene; and Fusion of the selected color image and the infrared image, so as to adjust the partial details of the color image according to the guidance of the partial details of the infrared image, so as to obtain an image with complete details of the camera scene. scene image. The dual-sensor camera system of claim 1, wherein the processor comprises: controlling at least one of the at least one color sensor and the at least one infrared sensor to capture at least one standard image of the camera scene using standard shooting conditions, and using the at least one standard image to identify the camera scene. The dual-sensor camera system of claim 1, wherein the processor includes, when the identified camera scene includes at least one defective area lacking texture detail, targeting an increase in the texture detail of the defective area The exposure time and the sensitivity are determined for each of the shooting conditions. The dual-sensor camera system of claim 3, wherein the processor includes, when the identified camera scene includes at least one dark area lacking texture detail, the exposure time and The sensitivity is determined by increasing at least one of the exposure time and the sensitivity to determine the exposure time and the sensitivity for each of the shooting conditions. The dual-sensor camera system of claim 3, wherein the processor includes, when the identified camera scene includes at least one highlight region lacking texture detail, the exposure time based on the standard shooting conditions and The sensitivity determines the exposure time and the sensitivity for each of the photographing conditions so as to reduce at least one of the exposure time and the sensitivity. The dual-sensor camera system of claim 3, further comprising an infrared projector, wherein the processor further comprises: The infrared projector is controlled to project infrared light, so as to increase the texture details in the infrared image captured by the at least one infrared sensor. The dual-sensor camera system of claim 3, wherein the processor further comprises: determining whether each of the infrared images includes the texture details of the defect area; and When none of the infrared images includes the texture details, control the at least one color sensor to capture a plurality of color images and capture a plurality of color images when using a plurality of exposures with a longer or shorter exposure time than the selected color image. High dynamic range (HDR) processing is performed to generate the scene image with the texture details of the defect area. The dual-sensor camera system of claim 1, wherein the feature domain transformation includes color space transformation or gradient transformation. A camera method for a dual-sensor camera system, the dual-sensor camera system includes at least one color sensor, at least one infrared sensor, and a processor, and the method includes the following steps: identifying a camera scene of the dual-sensor camera system; controlling the at least one color sensor and the at least one infrared sensor to capture a plurality of color images and a plurality of infrared images respectively using a plurality of shooting conditions suitable for the shooting scene, the shooting conditions include exposure Different combinations of time and sensitivity; calculating the difference between the signal-to-noise ratio of each of the color images and the signal-to-noise ratio of the infrared image, and the average brightness of each of the color images; Selecting the color image and the infrared image captured under the shooting condition where the difference of the signal-to-noise ratio is less than a signal-to-noise ratio threshold value and the luminance average value is greater than a luminance threshold value to perform feature domain conversion , to extract some details of the camera scene; and Fusion of the selected color image and the infrared image, so as to adjust the partial details of the color image according to the guidance of the partial details of the infrared image, so as to obtain an image with complete details of the camera scene. scene image. The method of claim 9, wherein the step of identifying the camera scene of the dual-sensor camera system comprises: controlling at least one of the at least one color sensor and the at least one infrared sensor to capture at least one standard image of the camera scene using standard shooting conditions, and using the at least one standard image to identify the camera scene. The method of claim 9, wherein after the step of identifying the camera scene of the dual-sensor camera system, further comprising: When the identified imaging scene includes at least one defect area lacking texture details, the exposure time and the sensitivity of each of the shooting conditions are determined with the goal of increasing the texture details of the defect area. The method according to claim 11, wherein the step of determining the exposure time and the sensitivity of each of the shooting conditions with the goal of increasing the texture details of the defect area comprises: When the identified shooting scene includes at least one dark area lacking texture details, based on the exposure time and the sensitivity of the standard shooting conditions, to increase at least one of the exposure time and the sensitivity In the method, the exposure time and the sensitivity are determined for each of the shooting conditions. The method according to claim 11, wherein the step of determining the exposure time and the sensitivity of each of the shooting conditions with the goal of increasing the texture details of the defect area comprises: When the identified camera scene includes at least one bright area lacking texture details, reducing at least one of the exposure time and the sensitivity based on the exposure time and the sensitivity of the standard shooting conditions way, the exposure time and the sensitivity of each of the shooting conditions are determined. The method of claim 11, wherein the dual-sensor camera system further comprises an infrared projector, and the method further comprises: The infrared projector is controlled to project infrared light, so as to increase the texture details in the infrared image captured by the at least one infrared sensor. The method according to claim 11, further comprising: determining whether each of the infrared images includes the texture details of the defect area; and When none of the infrared images includes the texture details, control the at least one color sensor to capture a plurality of color images and capture a plurality of color images when using a plurality of exposures with a longer or shorter exposure time than the selected color image. High dynamic range processing is performed to generate the scene image with the texture detail of the defect area. The method of claim 9, wherein the feature domain transformation includes color space transformation or gradient transformation.

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