A method, device, storage medium and product for collecting a fingerprint image

Abstract

This invention provides a method, device, storage medium, and product for acquiring fingerprint images. The method includes: acquiring a target screen brightness and the current screen brightness of the display screen when an exposure trigger condition is met; determining a target exposure time based on the current screen brightness and the target screen brightness; and enabling a fingerprint module to acquire fingerprints according to the target exposure time in a fixed exposure mode to obtain a fingerprint image. The fingerprint module is positioned below the display screen. Therefore, this invention calculates the target exposure time based on the acquired current screen brightness and target screen brightness, and then acquires fingerprint images according to this target exposure time. This achieves adjustment of the fingerprint acquisition exposure time to adapt to real-time changes in screen brightness, thereby improving the efficiency of fingerprint image acquisition.

Description

Technical Field

[0001] This invention relates to the field of fingerprint recognition technology, and in particular to a fingerprint image acquisition method, device, storage medium, and product. Background Technology

[0002] Currently, with the widespread application of fingerprint recognition technology, most electronic devices such as mobile phones and tablets are equipped with fingerprint modules (e.g., under-display fingerprint modules) to achieve fingerprint recognition functionality. Generally, when a fingerprint module is capturing a fingerprint image, the display screen needs to maintain a high brightness to illuminate the fingerprint and ensure that the obtained fingerprint image is clear enough.

[0003] However, in real-world applications, display brightness varies depending on ambient light. Related technologies often use an automatic exposure mode for the under-display fingerprint module. This mode determines the exposure time for each fingerprint image capture, adapting it to the current screen brightness to obtain a clear fingerprint image. However, the automatic exposure mode has a longer metering time, especially in low-light conditions, significantly reducing the fingerprint image capture speed and impacting the user experience. Summary of the Invention

[0004] In view of the above problems, embodiments of the present invention provide a fingerprint image acquisition method, device, storage medium and product, so as to overcome the problem of excessively long metering time in the automatic exposure mode while ensuring that the acquired fingerprint image is clear enough.

[0005] A first aspect of this invention provides a method for acquiring fingerprint images, comprising:

[0006] When the exposure trigger condition is met, obtain the target screen brightness and the current screen brightness of the display screen;

[0007] The target exposure time is determined based on the current screen brightness and the target screen brightness;

[0008] The fingerprint module is positioned below the display screen and performs fingerprint acquisition in a fixed exposure mode according to the target exposure time to obtain a fingerprint image.

[0009] Optionally, the method further includes:

[0010] During the fingerprint template input process, the fingerprint module performs fingerprint acquisition in automatic exposure mode to obtain a fingerprint template image;

[0011] The brightness of the display screen during the fingerprint template enrollment process is obtained, and the enrollment exposure time used by the fingerprint module for fingerprint acquisition in automatic exposure mode is obtained.

[0012] Determining the target exposure time based on the current screen brightness and the target screen brightness includes:

[0013] The target exposure time is determined based on the input screen brightness, the input exposure time, the current screen brightness, and the target screen brightness.

[0014] Optionally, determining the target exposure time based on the input screen brightness, the input exposure time, the current screen brightness, and the target screen brightness includes:

[0015] The code value of the fingerprint template image is determined based on the recorded screen brightness and the recorded exposure time;

[0016] The target exposure time is determined based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness.

[0017] Optionally, the fingerprint template image includes: N fingerprint template images obtained by collecting fingerprints from the same target finger during the fingerprint template acquisition process, where N is greater than or equal to 1;

[0018] Determining the code value of the fingerprint template image based on the input screen brightness and the input exposure time includes:

[0019] Take n as an integer from 1 to N, and determine the code value of the nth fingerprint template image of the target finger based on the nth recording screen brightness and the nth recording exposure time corresponding to the nth fingerprint template image of the target finger.

[0020] The code values ​​of N fingerprint template images of the target finger are fused together to obtain the code value of the fingerprint template image.

[0021] Optionally, the fingerprint template image includes: fingerprint template images of N different fingers obtained by collecting fingerprints from N different fingers during the fingerprint template enrollment process; determining the code value of the fingerprint template image based on the enrollment screen brightness and the enrollment exposure time includes:

[0022] Take n as an integer from 1 to N, and determine the code value of the fingerprint template image of each of the N different fingers based on the nth recording screen brightness and the nth recording exposure time corresponding to the fingerprint template image of the nth finger among the N different fingers.

[0023] The code values ​​of the fingerprint template images of the N different fingers are fused together to obtain the code value of the fingerprint template image.

[0024] Optionally, determining the target exposure time based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness includes:

[0025] Based on the current screen brightness and the target screen brightness, determine the reference brightness of the display screen during the process of changing from the current screen brightness to the target screen brightness;

[0026] The target exposure time is determined based on the code value of the fingerprint template image and the reference brightness.

[0027] Optionally, obtaining the target screen brightness includes:

[0028] Obtain the ambient light level of the environment in which the display screen is located;

[0029] The screen brightness that is adapted to the ambient light brightness is determined as the target screen brightness of the display screen.

[0030] The second aspect of this embodiment also provides a fingerprint image acquisition device, the device comprising:

[0031] The acquisition module is used to acquire the target screen brightness and the current screen brightness of the display screen when the exposure trigger condition is met.

[0032] The determining module is used to determine the target exposure time based on the current screen brightness and the target screen brightness;

[0033] The fingerprint acquisition module is used to enable the fingerprint module to acquire fingerprints in a fixed exposure mode according to the target exposure time, thereby obtaining a fingerprint acquisition image, wherein the fingerprint module is disposed below the display screen.

[0034] Optionally, the device further includes:

[0035] The fingerprint module is used to enable the fingerprint module to collect fingerprints in automatic exposure mode during the fingerprint template input process, thereby obtaining a fingerprint template image.

[0036] The screen brightness acquisition module is used to acquire the screen brightness of the display screen during the fingerprint template acquisition process, and to acquire the acquisition exposure time used by the fingerprint module to acquire fingerprints in automatic exposure mode.

[0037] The determining module includes:

[0038] The target exposure time determination submodule is used to determine the target exposure time based on the input screen brightness, the input exposure time, the current screen brightness, and the target screen brightness.

[0039] Optionally, the target exposure time determination submodule includes:

[0040] The image code value determination unit is used to determine the code value of the fingerprint template image based on the brightness of the input screen and the input exposure time;

[0041] The target exposure time determination unit is used to determine the target exposure time based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness.

[0042] Optionally, the fingerprint template image includes: N fingerprint template images obtained by collecting fingerprints from the same target finger during the fingerprint template acquisition process, where N is greater than or equal to 1;

[0043] The image code value determination unit includes:

[0044] The first determining subunit is used to take n as an integer from 1 to N, and determine the code value of the nth fingerprint template image of the target finger according to the nth recording screen brightness and the nth recording exposure time corresponding to the nth fingerprint template image of the target finger.

[0045] The second determining subunit is used to fuse the code values ​​of N fingerprint template images of the target finger to obtain the code value of the fingerprint template image.

[0046] Optionally, the fingerprint template image includes: fingerprint template images of N different fingers obtained by collecting fingerprints from N different fingers during the fingerprint template acquisition process; the image code value determination unit includes:

[0047] The third determining subunit is used to take n as an integer from 1 to N, and determine the code value of the fingerprint template image of each of the N different fingers according to the nth recording screen brightness and nth recording exposure time corresponding to the fingerprint template image of the nth finger among the N different fingers.

[0048] The fourth determining subunit is used to fuse the code values ​​of the fingerprint template images of the N different fingers to obtain the code value of the fingerprint template image.

[0049] Optionally, the target exposure time determination submodule includes:

[0050] A reference brightness determination unit is used to determine a reference brightness of the display screen during the process of changing from the current screen brightness to the target screen brightness, based on the current screen brightness and the target screen brightness.

[0051] The determining unit is used to determine the target exposure time based on the code value of the fingerprint template image and the reference brightness.

[0052] Optionally, the acquisition module includes:

[0053] An ambient light acquisition submodule is used to acquire the ambient light intensity of the environment in which the display screen is located;

[0054] The target screen brightness acquisition submodule is used to determine the screen brightness that is adapted to the ambient light brightness as the target screen brightness of the display screen.

[0055] A third aspect of the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the fingerprint image acquisition method described in the first aspect of the present invention.

[0056] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the fingerprint image acquisition method described in the first aspect of the present invention.

[0057] A fifth aspect of the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the fingerprint image acquisition method as described in the first aspect of the present invention.

[0058] This invention provides a fingerprint image acquisition method, device, storage medium, and product. The method includes: acquiring a target screen brightness and the current screen brightness of the display screen when an exposure trigger condition is met; determining a target exposure time based on the current screen brightness and the target screen brightness; and enabling a fingerprint module to acquire fingerprints according to the target exposure time in a fixed exposure mode to obtain a fingerprint image. The fingerprint module is positioned below the display screen. Therefore, this invention calculates the target exposure time based on the acquired current screen brightness and target screen brightness, enabling the fingerprint module to acquire fingerprint images according to the target exposure time in a fixed exposure mode. This achieves adjustment of the fingerprint acquisition exposure time to adapt to real-time changes in screen brightness, thereby improving the fingerprint image acquisition efficiency.

[0059] The specific beneficial effects are as follows:

[0060] 1) Improve the clarity of the acquired fingerprint images. In this embodiment of the invention, during fingerprint image acquisition, a target exposure time is calculated based on the current screen brightness and the target screen brightness. This allows the fingerprint module to acquire fingerprint images according to this target exposure time in a fixed exposure mode. Therefore, the exposure time used for each fingerprint image acquisition is adapted to the current screen brightness. The length of the exposure time affects the clarity of the acquired fingerprint image. This embodiment of the invention adapts the exposure time to the screen brightness for each fingerprint image acquisition, ensuring that the acquired fingerprint image is sufficiently clear.

[0061] 2) Improved fingerprint acquisition efficiency. Compared to methods that use automatic exposure mode to adapt to changes in screen brightness, this embodiment of the invention can directly calculate the target exposure time by obtaining the current screen brightness and the target screen brightness, omitting the metering step required by the automatic exposure mode. This achieves a rapid and accurate determination of the exposure time adapted to the current screen brightness, which is the target exposure time required for the fingerprint module to acquire fingerprint images in a fixed exposure mode, thus improving the efficiency of fingerprint acquisition. Attached Figure Description

[0062] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 This is a flowchart illustrating the steps of a fingerprint image acquisition method provided in an embodiment of the present invention;

[0064] Figure 2 This is a schematic diagram of the steps for fingerprint image acquisition provided in an embodiment of the present invention;

[0065] Figure 3 This is a schematic diagram of the steps for fingerprint template entry provided in an embodiment of the present invention;

[0066] Figure 4 This is a schematic diagram of the structure of a fingerprint image acquisition device provided in an embodiment of the present invention;

[0067] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0068] Exemplary embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0069] This invention provides a method for acquiring fingerprint images. This method can be applied to terminal devices such as mobile phones, tablets, and fingerprint scanners, and the terminal device has a display screen and a fingerprint module. The display screen can be a touchscreen, and the fingerprint module can be located below the display screen (i.e., an under-display fingerprint module). The fingerprint image acquisition method proposed in this embodiment can also be applied to fingerprint modules already present in terminal devices. The fingerprint image acquisition method provided by this invention will be described below with reference to the accompanying drawings.

[0070] Reference Figure 1 , Figure 1 A flowchart illustrating the steps of a fingerprint image acquisition method provided in this embodiment of the invention is shown below. Figure 1 As shown, the method includes:

[0071] Step S101: When the exposure trigger condition is met, obtain the target screen brightness and the current screen brightness of the display screen.

[0072] In this embodiment, the "satisfying the exposure trigger condition" means satisfying the trigger condition for the fingerprint module to perform exposure processing. Generally, the fingerprint module only performs exposure processing when acquiring fingerprint images. Therefore, this exposure trigger condition can be the exposure trigger condition when the fingerprint module acquires fingerprint images. Since foreign objects touching the display screen do not directly trigger fingerprint acquisition, and pressing or touching a finger on a non-collection area of ​​the display screen also does not trigger fingerprint acquisition, the exposure trigger condition can be specifically expressed as: when the screen is locked or when the display screen shows an interface that requires fingerprint recognition (e.g., an interface for payment based on fingerprint recognition results), it is detected that the user presses or touches their finger on the fingerprint collection area of ​​the display screen.

[0073] The current screen brightness indicates the brightness of the display screen at the current moment. Specifically, it refers to the screen brightness of the area outside the light spot on the display. This light spot represents the light emitted by the fingerprint collection area of ​​the display screen, which is directly opposite the fingerprint module. It is used to illuminate the fingerprint collection area in a high-brightness state to improve the clarity of the captured fingerprint image.

[0074] The screen brightness of a display is not a fixed value; it fluctuates within a certain range due to various external factors. For example, when the ambient light dims, the screen brightness decreases to adapt to the current environment and improve the user experience. Since the brightness of the display is controlled by relevant control components (e.g., ambient light sensors), this embodiment can directly obtain the current screen brightness by acquiring the brightness signal of the display.

[0075] Target screen brightness indicates the final brightness achieved by the display during the fingerprint image acquisition process. This is because the screen brightness may be unstable during fingerprint acquisition; for example, the display may increase its brightness to adapt to a brighter environment. The target screen brightness represents the final brightness achieved after this increase. Furthermore, this target screen brightness can be a pre-configured set value or range, or it can be directly obtained through the display's control components. Screen brightness is related to the code value of the acquired fingerprint image; generally, higher screen brightness results in a higher code value for the acquired fingerprint image.

[0076] In one embodiment, obtaining the target screen brightness includes:

[0077] Obtain the ambient light level of the environment in which the display screen is located;

[0078] The screen brightness that is adapted to the ambient light brightness is determined as the target screen brightness of the display screen.

[0079] In this embodiment, the ambient light brightness of the environment in which the display screen is located is obtained through relevant sensors of the display screen, such as an ambient light sensor. For the display screen, in order to improve the user experience, the ambient light sensor is used to collect the brightness of the external ambient light (i.e., the intensity of light), and the brightness of the display screen itself is adjusted according to the brightness of the external ambient light, adjusting the brightness of the display screen from the current screen brightness to the target screen brightness to adapt to the brightness of the ambient light, thereby avoiding problems such as display screen reflection and glare.

[0080] This embodiment proposes that, during fingerprint image acquisition, the ambient light intensity of the environment in which the display screen is located is obtained, and the target screen brightness of the display screen is determined based on the ambient light intensity. Specifically, a mapping relationship between the display screen brightness and the ambient light intensity can be obtained in advance. This mapping relationship can be expressed as a specific functional relationship or a mapping table. Therefore, after obtaining the ambient light intensity of the environment in which the display screen is located, the target screen brightness can be directly determined based on this mapping relationship. Furthermore, if the ambient light intensity of the environment in which the display screen is located does not change during the fingerprint image acquisition process, the brightness of the display screen itself will not change, and the obtained current screen brightness will be the same as the target screen brightness. This embodiment proposes to use the ambient light intensity of the environment in which the display screen is located to determine the screen brightness that matches the ambient light intensity as the target screen brightness. This fully considers the impact of changes in external ambient light intensity on screen brightness, thereby obtaining a more accurate target screen brightness, which is beneficial for determining the subsequent target exposure time and improving the clarity of the acquired fingerprint image.

[0081] Step S102: Determine the target exposure time based on the current screen brightness and the target screen brightness.

[0082] In this embodiment, the target exposure time refers to the exposure time required for this fingerprint image acquisition. For fingerprint image acquisition, the longer the exposure time, the higher the brightness of the acquired fingerprint image and the larger the code value of the acquired fingerprint image; the shorter the exposure time, the lower the brightness of the acquired fingerprint image and the smaller the code value of the acquired fingerprint image.

[0083] Step S103: The fingerprint module performs fingerprint acquisition in a fixed exposure mode according to the target exposure time to obtain a fingerprint acquisition image, wherein the fingerprint module is disposed below the display screen.

[0084] Fingerprint module exposure control logic generally falls into two categories: fixed exposure mode and automatic exposure mode. Fixed exposure mode involves capturing fingerprint images according to a fixed exposure time. However, this preset fixed exposure time doesn't account for changes in screen brightness, resulting in inconsistent code value distribution in the captured fingerprint images. This can easily lead to increased false positives for liveness detection and decreased fingerprint recognition success rate. Automatic exposure mode, on the other hand, involves the fingerprint module automatically performing light measurement each time a fingerprint image is captured. This measurement determines the required exposure time, and the fingerprint image is captured according to that time, resulting in a fixed target code value. However, the light measurement process in automatic exposure mode is time-consuming, reducing the speed of fingerprint image capture and impacting the user experience.

[0085] In this embodiment, after determining the target exposure time, the fingerprint module is exposed directly according to the target exposure time in a fixed exposure mode to obtain a fingerprint image, thereby realizing the fingerprint recognition function.

[0086] Reference Figure 2 , Figure 2 A schematic diagram of the steps for fingerprint image acquisition is shown, as follows: Figure 2 As shown, after fingerprint image acquisition begins, screen brightness information is obtained, including the current screen brightness and the target screen brightness. Then, based on the screen brightness information, the target exposure time is calculated, so that the fingerprint module acquires fingerprint images according to the target exposure time in a fixed exposure mode.

[0087] This embodiment directly determines the target exposure time by acquiring the current screen brightness and the target screen brightness. This allows the fingerprint module to acquire fingerprint images according to the target exposure time in a fixed exposure mode, thereby adjusting the fingerprint acquisition exposure time to adapt to real-time changes in screen brightness and improving the fingerprint image acquisition efficiency.

[0088] In this embodiment of the invention, during fingerprint image acquisition, a target exposure time is calculated based on the current screen brightness and the target screen brightness. This allows the fingerprint module to acquire fingerprint images according to this target exposure time in a fixed exposure mode. Therefore, the exposure time used for each fingerprint image acquisition is adapted to the current screen brightness. The length of the exposure time affects the clarity of the acquired fingerprint image; therefore, this embodiment of the invention adjusts the exposure time for each fingerprint image acquisition to ensure that the acquired fingerprint image is sufficiently clear.

[0089] Furthermore, compared to methods that use automatic exposure mode to adapt to changes in screen brightness, the embodiments of the present invention can directly calculate the target exposure time by obtaining the current screen brightness and the target screen brightness, omitting the metering steps required by the automatic exposure mode, and realizing the rapid and accurate determination of the exposure time adapted to the current screen brightness. This exposure time is the target exposure time required for the fingerprint module to perform fingerprint image acquisition in a fixed exposure mode, thereby improving the fingerprint image acquisition efficiency.

[0090] In one embodiment, the method further includes:

[0091] During the fingerprint template input process, the fingerprint module performs fingerprint acquisition in automatic exposure mode to obtain a fingerprint template image;

[0092] The brightness of the display screen during the fingerprint template enrollment process is obtained, and the enrollment exposure time used by the fingerprint module for fingerprint acquisition in automatic exposure mode is obtained.

[0093] Determine the target exposure time based on the current screen brightness and the target screen brightness, including:

[0094] The target exposure time is determined based on the input screen brightness, the input exposure time, the current screen brightness, and the target screen brightness.

[0095] Reference Figure 3 , Figure 3 A schematic diagram illustrating the steps of fingerprint template entry is shown, as follows: Figure 3 As shown, after starting fingerprint template enrollment, the fingerprint module performs fingerprint acquisition in automatic exposure mode, and then determines whether the enrollment was successful. If the acquired fingerprint template image is detected to be blurry, the enrollment is considered a failure, and the process returns to the first step to start enrollment again. If the acquired fingerprint template image is detected to be clear enough, the enrollment is considered successful, the corresponding screen brightness and exposure time are recorded, and finally, the fingerprint template enrollment ends.

[0096] In this embodiment, in addition to the current screen brightness and target screen brightness, the pre-stored input exposure time and corresponding input screen brightness can also be used to determine the target exposure time required for this fingerprint template image acquisition. Specifically, since the fingerprint template acquisition process is performed in automatic exposure mode, the fingerprint module uses automatic exposure mode for light metering to automatically determine the most suitable exposure time for the current brightness, ensuring that the code value of the acquired fingerprint template image is within the target range. In this embodiment, during fingerprint template acquisition, the fingerprint module acquires the fingerprint template image in automatic exposure mode, obtains the fingerprint template image, processes and stores it, and completes the fingerprint template acquisition.

[0097] In this embodiment, after each fingerprint template enrollment, the display screen brightness and the enrollment exposure time used for fingerprint acquisition are recorded during the enrollment process. The enrollment screen brightness represents the brightness of the display screen when the fingerprint template image is acquired during the current fingerprint template enrollment process; this brightness can be directly obtained from the display screen's brightness signal. The enrollment exposure time represents the exposure time determined in automatic exposure mode during fingerprint template enrollment, i.e., the exposure time used for fingerprint template image acquisition during this enrollment. Therefore, after each fingerprint template enrollment, an enrollment screen brightness and corresponding enrollment exposure time can be obtained.

[0098] This embodiment proposes to obtain the screen brightness of the display screen and the exposure time used by the fingerprint module for fingerprint acquisition in automatic exposure mode during the fingerprint acquisition process. The two (screen brightness and exposure time) are used to determine the target exposure time. The fingerprint recognition process is assisted and guided by the fingerprint template image acquisition process. That is, the target exposure time for fingerprint image acquisition is predicted by the screen brightness and exposure time determined during the fingerprint template image acquisition process, so as to ensure that the fingerprint image acquired by the fingerprint module in the fixed exposure mode according to the target exposure time is clearer.

[0099] In one embodiment, determining the target exposure time based on the input screen brightness, the input exposure time, the current screen brightness, and the target screen brightness includes:

[0100] The code value of the fingerprint template image is determined based on the recorded screen brightness and the recorded exposure time;

[0101] The target exposure time is determined based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness.

[0102] In this embodiment, the code value of the fingerprint template image is the code value of the fingerprint template image acquired in automatic exposure mode during fingerprint template enrollment. This code value can be the product of the screen brightness and the enrollment exposure time. In this embodiment, the code value of the fingerprint template image is used as the target code value of the image to be acquired in this fingerprint image acquisition. The target exposure time is determined based on the current screen brightness and the target screen brightness, so that the fingerprint module, in fixed exposure mode, acquires the fingerprint image according to the target exposure time, and the actual code value of the acquired fingerprint image is the same as the target code value, thereby ensuring the clarity of the acquired fingerprint image.

[0103] In one embodiment, determining the target exposure time based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness includes:

[0104] Based on the current screen brightness and the target screen brightness, determine the reference brightness of the display screen during the process of changing from the current screen brightness to the target screen brightness;

[0105] The target exposure time is determined based on the code value of the fingerprint template image and the reference brightness.

[0106] As mentioned earlier, the current screen brightness refers to the screen brightness at the current moment; the target screen brightness refers to the final brightness reached by the screen during this fingerprint image acquisition process. If the current screen brightness differs from the target screen brightness, the screen brightness will change from the current screen brightness to the target screen brightness during fingerprint image acquisition.

[0107] This embodiment determines a reference brightness based on the current screen brightness and the target screen brightness. Based on this reference brightness and the code value of the fingerprint template image, the target exposure time is obtained. The reference brightness is used to characterize the average brightness during the process of changing from the current screen brightness to the target screen brightness, representing the brightness of the display screen when fingerprint image acquisition is performed. For example, the average of the current screen brightness and the target screen brightness can be directly taken as the reference brightness. For instance, the target exposure time can be determined using the code value of the fingerprint template image and the reference brightness using the following formula:

[0108] T 目 =(T 录 ×L 录 ) / L 参

[0109] L 参 =(L 当 +L 目 ) / 2

[0110] Among them, L 参 For reference brightness; L 当 Current screen brightness; L 目 Target screen brightness; take L 当 and L 目 The average of both is the reference brightness L. 参 ;T 目 For the target exposure time, T 录 To record the exposure time, L 录 To record screen brightness, T 录 and L 录 The product of the two represents the code value of the fingerprint template image.

[0111] This embodiment combines the current screen brightness and the target screen brightness to determine a reference brightness. Then, it uses this reference brightness and the code value of the fingerprint template image to calculate the target exposure time. This simplifies the dynamic screen brightness information (current screen brightness and target screen brightness) into a specific value (reference brightness), facilitating subsequent calculation of the target exposure time, improving calculation efficiency, and accelerating fingerprint image acquisition.

[0112] In practical applications, fingerprint template entry can take many forms, such as multiple entries using a single fingerprint template or multiple fingerprint templates. The following examples illustrate these various fingerprint template entry scenarios.

[0113] In one embodiment, the fingerprint template image includes: N fingerprint template images obtained by collecting fingerprints from the same target finger during the fingerprint template acquisition process, where N is greater than or equal to 1;

[0114] The code value of the fingerprint template image is determined based on the screen brightness and the exposure time.

[0115] Take n as an integer from 1 to N, and determine the code value of the nth fingerprint template image of the target finger based on the nth recording screen brightness and the nth recording exposure time corresponding to the nth fingerprint template image of the target finger.

[0116] The code values ​​of N fingerprint template images of the target finger are fused together to obtain the code value of the fingerprint template image.

[0117] In this embodiment, multiple fingerprint template entries can be performed. Each successful fingerprint template entry results in a fingerprint template image, along with the corresponding entry exposure time and screen brightness. Specifically, during the fingerprint template entry process, multiple repeated fingerprint template entry operations are required for the same target finger. This means that fingerprint template images are captured multiple times for the same target finger, resulting in N fingerprint template images. N represents a constant, which can be the pre-set number of fingerprint template entries required, and N is greater than or equal to 1.

[0118] Let n be an integer from 1 to N. Based on the nth fingerprint template image of the target finger and the corresponding nth input screen brightness and nth input exposure time, the code value of the nth fingerprint template image of the target finger is determined. Specifically, for each fingerprint template input completed by the target finger, a corresponding fingerprint template image is obtained. The input screen brightness and input screen time at the time of fingerprint template image acquisition can be recorded and stored. Therefore, for each pair of input screen brightness and input screen time, the code value of the fingerprint template image can be calculated accordingly. Thus, each successful input of the target finger yields a code value for a fingerprint template image.

[0119] The code values ​​of N fingerprint template images of the target finger are fused to obtain the code value of the fingerprint template image. Since fingerprint template enrollment generates multiple fingerprint template image code values, this embodiment proposes that, after N fingerprint template enrollments of the target finger, the code values ​​of the resulting N fingerprint template images are fused to obtain the code value of the fingerprint template image. For example, the image code value can be represented as the product of the screen brightness and the enrollment exposure time. By fusing the code values ​​of the N fingerprint template images, the average of the N code values ​​can be taken as the final code value of the fingerprint template image.

[0120] This embodiment proposes that during the fingerprint template enrollment process, a single fingerprint template can be enrolled multiple times to obtain multiple sets of screen brightness and exposure time, thereby generating multiple fingerprint template image code values. Then, the code values ​​of these multiple fingerprint template images are fused to obtain the final code value of the fingerprint template image. Performing a single fingerprint module enrollment can easily generate abnormal data, resulting in fingerprint template image code values ​​that are too large or too small, thus affecting the subsequently acquired fingerprint images. This embodiment performs multiple and repeated enrollments of the fingerprint template and fuses the multiple code values, improving the accuracy of the final fingerprint template code value and further ensuring the clarity of the final acquired fingerprint image.

[0121] In one embodiment, the fingerprint template image includes: fingerprint template images of N different fingers obtained by collecting fingerprints from N different fingers during the fingerprint template enrollment process; and determining the code value of the fingerprint template image based on the enrollment screen brightness and the enrollment exposure time, including:

[0122] Take n as an integer from 1 to N, and determine the code value of the fingerprint template image of each of the N different fingers based on the nth recording screen brightness and the nth recording exposure time corresponding to the fingerprint template image of the nth finger among the N different fingers.

[0123] The code values ​​of the fingerprint template images of the N different fingers are fused together to obtain the code value of the fingerprint template image.

[0124] In this embodiment, during the fingerprint template enrollment process, fingerprint templates can be enrolled for each finger of the same user. If there are multiple users, fingerprint templates can also be enrolled for each finger of multiple users. Therefore, by acquiring fingerprint template images for N different fingers during the fingerprint template enrollment process, fingerprint template images for N different fingers can be obtained, where N represents a constant, greater than or equal to 1.

[0125] Let n be an integer from 1 to N. Based on the nth-th recording screen brightness and nth recording exposure time corresponding to the fingerprint template image of the nth finger among the N different fingers, the code value of each fingerprint template image for the N different fingers is determined. During fingerprint template recording, the recording screen brightness and recording exposure time for each finger are recorded, thereby determining the code value of the fingerprint template image for that finger based on the recording screen brightness and recording exposure time. For example, for a user who needs to record all the fingers of their right hand, the final result is fingerprint template images for 5 fingers and corresponding 5 code values. Furthermore, if each finger needs to be recorded multiple times, resulting in multiple fingerprint template images and multiple image code values, the average of the multiple image code values ​​is taken as the code value of the fingerprint template image for that finger.

[0126] The code values ​​of the fingerprint template images of the N different fingers are fused to obtain the code value of the fingerprint template image. Since fingerprints from multiple fingers need to be recorded, and each finger can obtain a code value from a fingerprint module image, this embodiment proposes to fuse the code values ​​of the fingerprint template images of the N different fingers to obtain the code value of the fingerprint template image. For example, the average of the code values ​​of the N different fingers can be taken as the code value of the final fingerprint template image.

[0127] This embodiment proposes that during the fingerprint template enrollment process, N fingerprint templates can be enrolled, resulting in the code values ​​of each of the N fingerprint template images. Then, the code values ​​of the N fingerprint template images are fused to obtain the code value of the final fingerprint template image. This embodiment considers that in practical applications, fingerprints from each of the user's fingers (fingerprint templates) can be enrolled, and differences may exist between fingers (fingerprint templates), leading to different code values ​​for each fingerprint template image. To avoid the influence of differences between different fingers (fingerprint templates), this embodiment fuses the code values ​​obtained from the separate enrollment of the N fingerprint templates, improving the accuracy of the final fingerprint template code value and further ensuring the clarity of the final acquired fingerprint image.

[0128] In one embodiment, during the fingerprint template enrollment process, N fingerprint templates can be enrolled, and each fingerprint template is enrolled N times, that is, N fingerprint images are acquired from N different fingers respectively, where N represents a constant, N greater than or equal to 1. Specifically, for each fingerprint template, following the method described in the above embodiment, N enrollments are performed to obtain N sets of enrollment screen brightness and enrollment exposure time, thereby obtaining N code values ​​for the fingerprint template image of that fingerprint template. Then, the obtained N code values ​​are fused to obtain the final code value of the fingerprint template image corresponding to that fingerprint template. According to the above method, each fingerprint template can obtain a fused fingerprint template image code value, and N fingerprint templates can obtain N fused fingerprint template image code values. Finally, the code values ​​of these N fingerprint template images are fused to determine the final fingerprint template image code value. Therefore, by performing N entries on a single fingerprint template, abnormal data from a single entry is avoided, and the data (code values ​​of fingerprint template images) of N fingerprint templates are fused together, thereby avoiding the influence of differences between fingerprint templates and further improving the accuracy of the final fingerprint template code values.

[0129] Furthermore, when a new user is added, their fingerprint needs to be recorded, resulting in the code values ​​of fingerprint template images for multiple fingers of the new user. In this case, the previously recorded fingerprint data can be deleted, and the code values ​​of the fingerprint template images of each finger of the new user can be fused together to obtain the code value of the fingerprint template image, which can be used for subsequent fingerprint image acquisition; alternatively, the code values ​​of the previously recorded fingerprint template images can be combined with the stored code values ​​of the fingerprint template images of each finger to obtain the code value of the fingerprint template image. This embodiment uses the fingerprint data of the new user (code values ​​of the fingerprint template image) to replace or combine the fingerprint data (code values ​​of the fingerprint template image) of the old user previously recorded, avoiding the situation where the fingerprints of the new user and the old user are different, and the code values ​​of the fingerprint template image determined based on the old user are not applicable to the new user, resulting in an unclear fingerprint image of the new user and fingerprint recognition failure.

[0130] This embodiment also provides a fingerprint image acquisition device, referring to... Figure 4 , Figure 4 A schematic diagram of a fingerprint image acquisition device is shown, as follows. Figure 4 As shown, the device includes:

[0131] The acquisition module is used to acquire the target screen brightness and the current screen brightness of the display screen when the exposure trigger condition is met.

[0132] The determining module is used to determine the target exposure time based on the current screen brightness and the target screen brightness;

[0133] The fingerprint acquisition module is used to enable the fingerprint module to acquire fingerprints in a fixed exposure mode according to the target exposure time, thereby obtaining a fingerprint acquisition image, wherein the fingerprint module is disposed below the display screen.

[0134] In one embodiment, the device further includes:

[0135] The fingerprint module is used to enable the fingerprint module to collect fingerprints in automatic exposure mode during the fingerprint template input process, thereby obtaining a fingerprint template image.

[0136] The screen brightness acquisition module is used to acquire the screen brightness of the display screen during the fingerprint template acquisition process, and to acquire the acquisition exposure time used by the fingerprint module to acquire fingerprints in automatic exposure mode.

[0137] The determining module includes:

[0138] The target exposure time determination submodule is used to determine the target exposure time based on the input screen brightness, the input exposure time, the current screen brightness, and the target screen brightness.

[0139] In one embodiment, the target exposure time determination submodule includes:

[0140] The image code value determination unit is used to determine the code value of the fingerprint template image based on the brightness of the input screen and the input exposure time;

[0141] The target exposure time determination unit is used to determine the target exposure time based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness.

[0142] In one embodiment, the fingerprint template image includes: N fingerprint template images obtained by collecting fingerprints from the same target finger during the fingerprint template acquisition process, where N is greater than or equal to 1;

[0143] The image code value determination unit includes:

[0144] The first determining subunit is used to take n as an integer from 1 to N, and determine the code value of the nth fingerprint template image of the target finger according to the nth recording screen brightness and the nth recording exposure time corresponding to the nth fingerprint template image of the target finger.

[0145] The second determining subunit is used to fuse the code values ​​of N fingerprint template images of the target finger to obtain the code value of the fingerprint template image.

[0146] In one embodiment, the fingerprint template image includes: fingerprint template images of N different fingers obtained by collecting fingerprints from N different fingers during the fingerprint template acquisition process; the image code value determination unit includes:

[0147] The third determining subunit is used to take n as an integer from 1 to N, and determine the code value of the fingerprint template image of each of the N different fingers according to the nth recording screen brightness and nth recording exposure time corresponding to the fingerprint template image of the nth finger among the N different fingers.

[0148] The fourth determining subunit is used to fuse the code values ​​of the fingerprint template images of the N different fingers to obtain the code value of the fingerprint template image.

[0149] In one embodiment, the target exposure time determination submodule includes:

[0150] A reference brightness determination unit is used to determine a reference brightness of the display screen during the process of changing from the current screen brightness to the target screen brightness, based on the current screen brightness and the target screen brightness.

[0151] The determining unit is used to determine the target exposure time based on the code value of the fingerprint template image and the reference brightness.

[0152] In one embodiment, the acquisition module includes:

[0153] An ambient light acquisition submodule is used to acquire the ambient light intensity of the environment in which the display screen is located;

[0154] The target screen brightness acquisition submodule is used to determine the screen brightness that is adapted to the ambient light brightness as the target screen brightness of the display screen.

[0155] This invention also provides an electronic device, with reference to... Figure 5 , Figure 5 This is a schematic diagram of the structure of the electronic device proposed in an embodiment of the present invention. Figure 5 As shown, the electronic device 100 includes a memory 110 and a processor 120. The memory 110 and the processor 120 are connected via a bus for communication. The memory 110 stores a computer program that can run on the processor 120 to implement a fingerprint image acquisition method disclosed in this embodiment of the invention.

[0156] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements a fingerprint image acquisition method disclosed in this invention.

[0157] This invention also provides a computer program product, including a computer program that, when executed by a processor, implements a fingerprint image acquisition method as disclosed in this invention.

[0158] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0159] Embodiments of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods, apparatuses, electronic devices, readable storage media, and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0160] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0161] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0162] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0163] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0164] The foregoing has provided a detailed description of the fingerprint image acquisition method, device, storage medium, and product provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method of capturing a fingerprint image, characterized by, The method includes: During the fingerprint template input process, the fingerprint module performs fingerprint acquisition in automatic exposure mode to obtain a fingerprint template image; The brightness of the display screen during the fingerprint template enrollment process is obtained, and the enrollment exposure time used by the fingerprint module for fingerprint acquisition in automatic exposure mode is obtained. When the exposure trigger condition is met, obtain the target screen brightness and the current screen brightness of the display screen; Determining the target exposure time based on the current screen brightness and the target screen brightness includes: determining the code value of the fingerprint template image based on the input screen brightness and the input exposure time; determining the target exposure time based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness; wherein the code value is the product of the input screen brightness and the input exposure time. The fingerprint module is positioned below the display screen and performs fingerprint acquisition in a fixed exposure mode according to the target exposure time to obtain a fingerprint image.

2. The data acquisition method according to claim 1, characterized in that, The fingerprint template images include: N fingerprint template images obtained by collecting fingerprints from the same target finger during the fingerprint template input process, where N is greater than or equal to 1; Determining the code value of the fingerprint template image based on the input screen brightness and the input exposure time includes: Take n as an integer from 1 to N, and determine the code value of the nth fingerprint template image of the target finger based on the nth recording screen brightness and the nth recording exposure time corresponding to the nth fingerprint template image of the target finger. The code values ​​of N fingerprint template images of the target finger are fused together to obtain the code value of the fingerprint template image.

3. The data acquisition method according to claim 1, characterized in that, The fingerprint template image includes: fingerprint template images of N different fingers obtained by collecting fingerprints from N different fingers during the fingerprint template input process; Determining the code value of the fingerprint template image based on the input screen brightness and the input exposure time includes: Take n as an integer from 1 to N, and determine the code value of the fingerprint template image of each of the N different fingers based on the nth recording screen brightness and the nth recording exposure time corresponding to the fingerprint template image of the nth finger among the N different fingers. The code values ​​of the fingerprint template images of the N different fingers are fused together to obtain the code value of the fingerprint template image.

4. The data acquisition method according to claim 1, characterized in that, The step of determining the target exposure time based on the code value of the fingerprint template image, the current screen brightness, and the target screen brightness includes: Based on the current screen brightness and the target screen brightness, determine the reference brightness of the display screen during the process of changing from the current screen brightness to the target screen brightness; The target exposure time is determined based on the code value of the fingerprint template image and the reference brightness.

5. The data acquisition method according to any one of claims 1-4, characterized in that, The process of obtaining the target screen brightness includes: Obtain the ambient light level of the environment in which the display screen is located; The screen brightness that is adapted to the ambient light brightness is determined as the target screen brightness of the display screen.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the fingerprint image acquisition method according to any one of claims 1-5.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the fingerprint image acquisition method as described in any one of claims 1-5.

8. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the fingerprint image acquisition method as described in any one of claims 1-5.

Images