An exposure time calibration method, device and product of a fingerprint module

Abstract

This invention provides a method, apparatus, and product for calibrating the exposure time of a fingerprint module. The method includes: acquiring an exposure time sequence, which includes multiple input exposure times, where each input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode; determining the calibrated exposure time based on the multiple input exposure times in the exposure time sequence; and updating the calibrated exposure time to the fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode. This invention obtains the calibrated exposure time based on the input exposure time obtained in automatic exposure mode and uses it as the fixed exposure time, enabling subsequent fingerprint acquisition to be performed according to this calibrated exposure time, thus improving the accuracy of the exposure time.

Description

Technical Field

[0001] This invention relates to the field of fingerprint recognition technology, and in particular to a method, apparatus and product for calibrating the exposure time of a fingerprint module. 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 for fingerprint recognition. Generally, the fingerprint recognition scheme in these modules uses a fixed exposure mode, meaning that fingerprint images are acquired using a fixed exposure time. This fixed exposure time is typically calibrated using a mold testing process on the production line.

[0003] However, the current approach of setting a fixed exposure time directly during production testing ignores the fact that this exposure time cannot adapt to differences in different fingers, screens, and environments. This results in significant variations in the fingerprint image code values ​​across different people and machines, reducing fingerprint recognition success rates and impacting the user experience. Therefore, it is necessary to develop a method, device, and product for calibrating the exposure time of fingerprint modules to improve the accuracy of exposure time. Summary of the Invention

[0004] In view of the above problems, embodiments of the present invention provide a method, apparatus and product for calibrating the exposure time of a fingerprint module, so as to overcome the above problems or at least partially solve the above problems.

[0005] A first aspect of the present invention provides a method for calibrating the exposure time of a fingerprint module, comprising:

[0006] Obtain an exposure time series, which includes multiple input exposure times. One input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode.

[0007] Based on the multiple recorded exposure times in the exposure time series, determine the exposure time after this calibration;

[0008] The fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode is updated to the exposure time after this calibration.

[0009] Optionally, the exposure time after calibration is determined based on multiple recorded exposure times in the exposure time series, including:

[0010] Candidate exposure times are obtained based on the duration of each of the multiple recorded exposure times in the exposure time series;

[0011] Based on the candidate exposure times, determine the exposure time after this calibration.

[0012] Optionally, the exposure time after this calibration is determined based on the candidate exposure times, including:

[0013] If this calibration is not the first calibration, obtain the exposure time after one or more historical calibrations;

[0014] The exposure time after this calibration is determined based on the candidate exposure time and the exposure time after one or more historical calibrations.

[0015] Optionally, the exposure time after this calibration is determined based on the candidate exposure times, including:

[0016] In the case that this calibration is the first calibration, the candidate exposure time will be determined as the exposure time after this calibration.

[0017] Optionally, candidate exposure times are obtained based on the duration of each of the multiple recorded exposure times in the exposure time series, including:

[0018] According to the order of duration from longest to shortest, the first N recorded exposure times are obtained from the exposure time series;

[0019] Based on the ratio between each of the first N recorded exposure times and the next adjacent recorded exposure time, one of the first N recorded exposure times is determined as the candidate exposure time.

[0020] Optionally, one of the first N recorded exposure times is determined as the candidate exposure time, including:

[0021] For the first N recorded exposure times, determine the ratio between each recorded exposure time and the next adjacent recorded exposure time in descending order of duration;

[0022] The candidate exposure time is determined as the one in which the ratio between the first of the first N recorded exposure times and the next adjacent recorded exposure time satisfies the target condition.

[0023] If, among the first N recorded exposure times, there is no ratio between the time record time and the next adjacent recorded exposure time that satisfies the target condition, the smallest recorded exposure time among the first N recorded exposure times is determined as the candidate exposure time.

[0024] Optionally, the target condition is that the ratio between two adjacent recorded exposure times is less than a target threshold.

[0025] Optionally, the exposure mode of the fingerprint module is set to a fixed exposure mode by default; it also includes:

[0026] Detect whether an exposure time calibration request for the fingerprint module has been received;

[0027] Obtain the exposure time series, including:

[0028] Upon detecting an exposure time calibration request for the fingerprint module, the exposure mode of the fingerprint module is switched from fixed exposure mode to automatic exposure mode;

[0029] The fingerprint module performs a fingerprint registration once by pressing a finger on the fingerprint recognition area of ​​the screen, and obtains a registration exposure time. Multiple registration exposure times constitute the exposure time sequence.

[0030] A second aspect of the present invention also provides an exposure time calibration device for a fingerprint module, comprising:

[0031] The acquisition module is used to acquire an exposure time series, which includes multiple input exposure times. One input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode.

[0032] The determination module is used to determine the exposure time after this calibration based on multiple recorded exposure times in the exposure time series;

[0033] The update module is used to update the fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode to the exposure time after this calibration.

[0034] Optionally, the determining module includes:

[0035] The candidate exposure time determination submodule is used to obtain candidate exposure times based on the duration of each of the multiple recorded exposure times in the exposure time sequence;

[0036] The first determining submodule is used to determine the exposure time after this calibration based on the candidate exposure times.

[0037] Optionally, the first determining submodule includes:

[0038] The historical exposure time acquisition unit is used to acquire the exposure time after one or more historical calibrations when the current calibration is not the first calibration.

[0039] The first determining unit is used to determine the exposure time after the current calibration based on the candidate exposure time and the exposure time after one or more historical calibrations.

[0040] Optionally, the first determining submodule includes:

[0041] The second determining unit is used to determine the candidate exposure time as the exposure time after this calibration when this calibration is the first calibration.

[0042] Optionally, the candidate exposure time determination submodule includes:

[0043] The first acquisition unit is used to acquire the first N recorded exposure times from the exposure time sequence in descending order of duration.

[0044] The ratio determination unit is used to determine one of the first N recorded exposure times as the candidate exposure time based on the ratio between each recorded exposure time and the next adjacent recorded exposure time.

[0045] Optionally, the ratio determination unit includes:

[0046] The first ratio determination subunit is used to determine the ratio between each recorded exposure time and the next adjacent recorded exposure time in descending order of duration for the first N recorded exposure times.

[0047] The second ratio determination subunit is used to determine the candidate exposure time as the first of the first N recorded exposure times whose ratio with the next adjacent recorded exposure time satisfies the target condition.

[0048] The third ratio determination subunit is used to determine the smallest recording exposure time among the first N recording exposure times as the candidate exposure time, provided that there is no ratio between the first N recording exposure times and the next adjacent recording exposure time that satisfies the target condition.

[0049] Optionally, the target condition is that the ratio between two adjacent recorded exposure times is less than a target threshold.

[0050] Optionally, the exposure mode of the fingerprint module is set to a fixed exposure mode by default; the device further includes:

[0051] The detection module is used to detect whether an exposure time calibration request for the fingerprint module has been received;

[0052] The acquisition module includes:

[0053] The switching submodule is used to switch the exposure mode of the fingerprint module from a fixed exposure mode to an automatic exposure mode when an exposure time calibration request for the fingerprint module is detected.

[0054] The exposure time series acquisition submodule is used to perform a fingerprint enrollment on a finger pressing the fingerprint recognition area of ​​the screen through the fingerprint module, and obtain an enrollment exposure time. Multiple enrollment exposure times constitute the exposure time series.

[0055] A third aspect of the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps in the exposure time calibration method for a fingerprint module described in the first aspect of the present invention.

[0056] A fourth aspect of the present invention also provides a computer-readable storage medium having a computer program / instructions stored thereon, which, when executed by a processor, implements the steps in the exposure time calibration method for a fingerprint module described in the first aspect of the present invention.

[0057] The fifth aspect of this invention also provides a computer program product, which, when run on an electronic device, enables a processor to execute the steps in the exposure time calibration method for a fingerprint module described in the first aspect of this invention.

[0058] This invention provides a method, apparatus, and product for calibrating the exposure time of a fingerprint module. The method includes: acquiring an exposure time sequence, which includes multiple input exposure times, where each input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode; determining the calibrated exposure time based on the multiple input exposure times in the exposure time sequence; and updating the fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode to the calibrated exposure time. This invention obtains the calibrated exposure time based on the input exposure time obtained in automatic exposure mode and uses it as the fixed exposure time. This allows subsequent fingerprint acquisition to be performed according to the calibrated exposure time, improving the accuracy of the exposure time. This achieves adaptive optimization of issues such as differences in reflectivity of different fingers, decreased luminous efficiency due to screen aging, and discoloration due to aging of the test head (i.e., test component, such as a flesh-colored rubber tip), thereby improving the fingerprint recognition pass rate. Attached Figure Description

[0059] 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.

[0060] Figure 1This is a flowchart illustrating the steps of an exposure time calibration method for a fingerprint module provided in an embodiment of the present invention;

[0061] Figure 2 This is a calibration flowchart for a fixed exposure time provided in an embodiment of the present invention;

[0062] Figure 3 This is a schematic diagram of the structure of an exposure time calibration device for a fingerprint module provided in an embodiment of the present invention;

[0063] Figure 4 This is a schematic diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0064] 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.

[0065] This invention provides a method for calibrating the exposure time of a fingerprint module, referring to... Figure 1 , Figure 1 A flowchart illustrating the steps of an exposure time calibration method for a fingerprint module provided in an embodiment of the present invention is shown below. Figure 1 As shown, the method includes:

[0066] Step S101: Obtain the exposure time series, which includes multiple input exposure times. One input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode.

[0067] In this embodiment, the exposure time sequence refers to a sequence composed of multiple fingerprint entry exposure times. Each fingerprint entry exposure time refers to the exposure time used by the fingerprint module to complete one fingerprint entry in automatic exposure mode. Each time a fingerprint entry is completed, the corresponding exposure time is recorded as the fingerprint entry exposure time and stored in the exposure time sequence. Specifically, one fingerprint entry refers to the fingerprint module acquiring a fingerprint image each time the user presses their finger, thus completing one fingerprint entry. For example, if fingerprint entry requires repeated pressing of the finger 20 times to complete 20 fingerprint entries, then 20 fingerprint entry exposure times are obtained and stored in the exposure time sequence.

[0068] Automatic exposure mode allows the fingerprint module to automatically adjust the exposure time so that the image code value of the acquired fingerprint image is a fixed target code value (this target code value is an accurate parameter or parameter range), or in other words, to maintain a consistent brightness in the acquired fingerprint image. This target code value represents the brightness of the image; the longer the exposure time, the larger the acquired image code value, and the brighter the image; conversely, the shorter the exposure time, the smaller the acquired image code value, and the darker the image.

[0069] It's important to understand that automatic exposure mode requires a longer time to acquire fingerprint images. In practical applications, automatic exposure mode is often avoided; instead, fixed exposure mode is used, which acquires fingerprint images at a fixed exposure time. Typically, during the production testing phase of fingerprint modules, a flesh-colored rubber test component is used to test the fingerprint module's image acquisition. Based on the test results, a fixed exposure time for the fingerprint module in fixed exposure mode is determined. This solution addresses differences in screen transmittance, module aperture, and sensor sensitivity during production testing. However, in practical applications, it doesn't consider differences in reflectivity between different fingers, decreased screen luminous efficiency due to aging, and discoloration of the flesh-colored rubber tip. This results in inconsistent image code value distributions in fingerprint images acquired by the fingerprint module under this fixed exposure time, regardless of the user or the device used. This can easily lead to increased false positives for liveness detection and decreased recognition success rate, negatively impacting the user experience.

[0070] Step S102: Determine the exposure time after this calibration based on the multiple recorded exposure times in the exposure time series.

[0071] Since the fingerprint enrollment exposure time is the exposure time used when enrolling fingerprints in automatic exposure mode, this enrollment exposure time is adapted to the reflectivity of the finger, the luminosity of the screen, and the ambient brightness during fingerprint enrollment. It means that when enrolling fingerprints, a clear fingerprint image belonging to the target code value can be obtained according to this exposure time.

[0072] Step S103: Update the fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode to the exposure time after this calibration.

[0073] In this embodiment, the fixed exposure time in the fixed exposure mode is updated using the calibrated exposure time, making the updated fixed exposure time more adaptable to the application environment. This addresses issues such as differences in reflectivity between different people's fingers, decreased luminous efficiency due to screen aging, and discoloration of the flesh-colored rubber tip due to aging. For example, taking a mobile phone's fingerprint module as an example, when the phone is first manufactured, the screen is fully functional, and the screen's luminous efficiency remains at a high standard. At this time, the fixed exposure time is 0.5s, meaning that each time a fingerprint image is captured, the fingerprint module uses a fixed exposure time of 0.5s to take a picture, resulting in a clear fingerprint image. As the phone is used for a longer period, the screen ages, and the screen transmittance and luminous efficiency decrease. At this time, if the fingerprint image is still captured using a fixed exposure time of 0.5s, the resulting image will be darker and more likely to be unclear. According to the exposure time calibration method proposed in this embodiment, the exposure time after calibration is determined to be 0.8s based on multiple recorded exposure times in the exposure time sequence, thereby updating the fixed exposure time from 0.5s to 0.8s, solving the impact of screen aging. When performing fingerprint recognition in the future, fingerprint image acquisition is performed according to the updated fixed exposure time, ensuring the clarity of the acquired fingerprint image and improving the probability of successful fingerprint recognition.

[0074] In this embodiment, the fingerprint module can automatically perform a calibration update of the fixed exposure time according to the above steps each time a fingerprint is enrolled, or the user can actively initiate the calibration update of the fixed exposure time of the fingerprint module.

[0075] Therefore, this embodiment obtains an exposure time series, which includes multiple enrollment exposure times. One enrollment exposure time is the exposure time used by the fingerprint module to complete one fingerprint enrollment in automatic exposure mode. Based on the multiple enrollment exposure times in the exposure time series, the calibrated exposure time is determined. The fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode is updated to the calibrated exposure time. This embodiment obtains the calibrated exposure time based on the enrollment exposure time obtained in automatic exposure mode and uses it as the fixed exposure time. This allows subsequent fingerprint acquisition to be completed according to the calibrated exposure time, improving the accuracy of the exposure time. This achieves adaptive optimization of issues such as differences in reflectivity of different fingers, decreased luminous efficiency due to screen aging, and discoloration due to aging of the test head (i.e., the test component, such as a flesh-colored rubber tip), thereby improving the fingerprint recognition pass rate.

[0076] In one embodiment, determining the calibrated exposure time based on multiple recorded exposure times in the exposure time series includes:

[0077] Candidate exposure times are obtained based on the duration of each of the multiple recorded exposure times in the exposure time series;

[0078] Based on the candidate exposure times, determine the exposure time after this calibration.

[0079] In this embodiment, a candidate exposure time is first determined based on the duration of the recorded exposure time. After determining the candidate exposure time, it is also necessary to adjust it based on the previous calibration history of the fingerprint module. In this way, the exposure time after this calibration is determined based on the candidate exposure time, so as to update the fixed exposure time to the exposure time after this calibration.

[0080] In one embodiment, determining the calibrated exposure time based on the candidate exposure times includes:

[0081] If this calibration is not the first calibration, obtain the exposure time after one or more historical calibrations;

[0082] The exposure time after this calibration is determined based on the candidate exposure time and the exposure time after one or more historical calibrations.

[0083] In this embodiment, the current calibration is not the first calibration, meaning that the fingerprint module has undergone one or more calibrations for the fixed exposure time before the current moment. In this case, after determining the candidate exposure time based on the entered exposure time, the candidate exposure time is adjusted using the historical data from previous calibrations (which can be the fixed exposure time after previous calibrations), thereby obtaining the exposure time after this calibration, making the exposure time after this calibration more accurate and reliable.

[0084] In this embodiment, when determining the exposure time after the current calibration based on the candidate exposure time and the exposure time after one or more historical calibrations, the average value of the candidate exposure time and the exposure time after one or more historical calibrations can be taken as the exposure time after the current calibration. For example, after determining the candidate exposure time to be 1.2s, it is found that the fingerprint module underwent two calibrations before. The fixed exposure time after the first calibration was 0.7s, and the exposure time after the second calibration was 0.8s. Therefore, by taking the average value, the exposure time after the current calibration is determined to be 0.9s, and the fixed exposure time can be updated to 0.9s. In this way, adjusting the candidate exposure time using historical calibration data makes the exposure time after the current calibration more accurate and reliable. Furthermore, if the fingerprint module has undergone multiple calibrations, the exposure time after the most recent N calibrations can be selected, where N represents an arbitrary constant and can be set according to actual conditions. In this embodiment, there is no limitation on this setting.

[0085] In one embodiment, determining the calibrated exposure time based on the candidate exposure times includes:

[0086] In the case that this calibration is the first calibration, the candidate exposure time will be determined as the exposure time after this calibration.

[0087] In this embodiment, when the fingerprint module has not undergone exposure time calibration before, i.e., this calibration is the first calibration, it is impossible to adjust the candidate exposure time based on historical data from previous calibrations. The candidate exposure time can be directly determined as the exposure time after this calibration, and then the fixed exposure time can be updated based on this time.

[0088] In one embodiment, candidate exposure times are obtained based on the duration of each of the multiple recorded exposure times in the exposure time series, including:

[0089] According to the order of duration from longest to shortest, the first N recorded exposure times are obtained from the exposure time series;

[0090] Based on the ratio between each of the first N recorded exposure times and the next adjacent recorded exposure time, one of the first N recorded exposure times is determined as the candidate exposure time.

[0091] In this embodiment, since the exposure time series stores exposure times recorded during multiple fingerprint entries, there is a risk of excessive and repetitive exposure time data. Therefore, this embodiment proposes sorting multiple fingerprint exposure times in descending order of duration, and selecting the top N longest exposure times to calculate candidate exposure times. For example, the three longest exposure times in the exposure time series can be obtained.

[0092] After determining N recorded exposure times, one of these N recorded exposure times is selected as a candidate exposure time based on the ratio between two adjacent recorded exposure times. Then, the exposure time after calibration is determined based on this candidate exposure time. This ratio refers to the ratio between two adjacent recorded exposure times when sorted by duration from longest to shortest. For example, if N equals 3, and the three longest recorded exposure times in the exposure time sequence are obtained and sorted by duration from longest to shortest as t1, t2, and t3, then the ratios are the ratio between t1 and t2, and the ratio between t2 and t3.

[0093] This embodiment selects a candidate exposure time from N exposure times based on a ratio because the fingerprint enrollment environment is unstable, and the resulting exposure time is also unstable. For example, if a user enrolls their fingerprint outdoors in bright ambient light, there may be light leakage due to the finger pressing off-center during fingerprint enrollment, resulting in an exposure time that is too short in automatic exposure mode. Alternatively, in occasional cases, a high-brightness timing error may occur, causing the screen to not be highlighted during fingerprint enrollment, resulting in an excessively long exposure time. Therefore, this embodiment proposes calculating the ratio between two adjacent exposure times to determine whether the exposure time is abnormal (too long or too short), thereby ensuring the accuracy of the obtained candidate exposure time and thus ensuring the accuracy of the determined exposure time after calibration.

[0094] In one embodiment, determining one of the first N recorded exposure times as the candidate exposure time includes:

[0095] For the first N recorded exposure times, determine the ratio between each recorded exposure time and the next adjacent recorded exposure time in descending order of duration;

[0096] The candidate exposure time is determined as the one in which the ratio between the first of the first N recorded exposure times and the next adjacent recorded exposure time satisfies the target condition.

[0097] If, among the first N recorded exposure times, there is no ratio between the time record time and the next adjacent recorded exposure time that satisfies the target condition, the smallest recorded exposure time among the first N recorded exposure times is determined as the candidate exposure time.

[0098] In this embodiment, the first N recorded exposure times are sorted in descending order of duration, and the ratio between each recorded exposure time and the next adjacent recorded exposure time is obtained. Following the previous example, the recorded exposure times are t1, t2, and t3 in descending order of duration. First, the ratio between t1 and t2 is obtained, and then the ratio between t2 and t3 is obtained. If the ratio between t1 and t2 meets the target condition, it is not necessary to obtain the ratios of subsequent recorded exposure times; t1 is directly determined as the candidate exposure time. If the ratio between t1 and t2 does not meet the target condition, the ratio between t2 and t3 needs to be obtained. If the ratio between t2 and t3 meets the target condition, t2 is determined as the candidate exposure time. If the ratio between t2 and t3 does not meet the target condition, the minimum value among t1, t2, and t3 is determined as the candidate exposure time, as explained below. Therefore, the recorded exposure time with the longest duration and the ratio that meets the target condition can be determined as the candidate exposure time. If the ratio meets the target condition, it means that the recorded exposure time is a normal recorded exposure time and is not a recorded exposure time recorded under abnormal circumstances such as highlight timing error or strong light misalignment. Therefore, it is determined as a candidate exposure time.

[0099] If none of the first N recorded exposure times has a ratio that satisfies the target condition, then the recorded exposure time with the shortest duration is determined as the candidate exposure time. For example, still assuming N is 3, the recorded exposure times are t1, t2, and t3 in descending order of duration. If neither the ratio between t1 and t2 nor the ratio between t2 and t3 satisfies the target condition, then the minimum value among t1, t2, and t3 (for example, the minimum value could be t3) is determined as the candidate exposure time.

[0100] In one embodiment, the target condition is that the ratio between two adjacent recorded exposure times is less than a target threshold.

[0101] In this embodiment, whether the ratio between each recorded exposure time and the next adjacent recorded exposure time meets the target condition is determined based on whether the ratio between these two recorded exposure times is less than a target threshold. If the target condition is not met, it indicates that the recorded exposure time with the longer duration among the two recorded exposure times is an abnormal recorded exposure time and cannot be determined as a candidate exposure sequence. Specifically, if the ratio between two recorded exposure times does not meet the target condition, that is, the ratio between the two recorded exposure times exceeds the target threshold, it indicates that the duration difference between these two adjacent recorded exposure times is large, and at least one of these two adjacent recorded exposure times is abnormal, such as recorded exposure times recorded under abnormal situations such as highlight timing errors or strong light misalignment. The target threshold can be preset based on experimental data and experience. For example, if the target threshold is set to 1.1, and it is determined that the ratio between t1 and t2 is 1.2, exceeding the target threshold of 1.1, then the ratio between t1 and t2 does not meet the target condition. Similarly, if the ratio between t2 and t3 is determined to be 0.9, which does not exceed the target threshold of 1.1, then the ratio between t2 and t3 satisfies the target condition.

[0102] In one embodiment, the fingerprint module's exposure mode is set to a fixed exposure mode by default; it also includes:

[0103] Detect whether an exposure time calibration request for the fingerprint module has been received;

[0104] Obtain the exposure time series, including:

[0105] Upon detecting an exposure time calibration request for the fingerprint module, the exposure mode of the fingerprint module is switched from fixed exposure mode to automatic exposure mode;

[0106] The fingerprint module performs a fingerprint registration once by pressing a finger on the fingerprint recognition area of ​​the screen, and obtains a registration exposure time. Multiple registration exposure times constitute the exposure time sequence.

[0107] In this embodiment, refer to Figure 2 , Figure 2 A calibration flowchart with a fixed exposure time is shown, such as... Figure 2 As shown, the fingerprint module detects whether it has received an exposure time calibration request for the fingerprint module. If a calibration request is received, then... Figure 2The first step is to begin fingerprint enrollment. Since the fingerprint module is typically set to a fixed exposure mode when acquiring fingerprint images, upon detecting an exposure time calibration request for that fingerprint module, it needs to switch from fixed exposure mode to automatic exposure mode, which the fingerprint module automatically sets to. Next, the user presses their finger on the corresponding fingerprint recognition area to enroll their fingerprint. The fingerprint module then enrolls the finger on the fingerprint recognition area of ​​the screen. If enrollment is unsuccessful, it automatically returns to the previous step, and the user presses their finger again, allowing the fingerprint module to enroll the fingerprint once more. If enrollment is successful, an enrollment exposure time is obtained and recorded by the fingerprint module. Because fingerprint enrollment is usually performed multiple times, the fingerprint module determines whether enrollment is complete based on the number of enrollments. If enrollment is incomplete, it returns to the third step, where the user presses their finger on the corresponding fingerprint recognition area again to enroll the fingerprint. If the target number of enrollments is reached, enrollment is complete, and the fingerprint module obtains multiple enrollment exposure times, forming the exposure time sequence. The fingerprint module automatically enters the subsequent calibration and exposure process. Based on the obtained exposure time sequence, it completes the exposure time calibration and finally ends the recording. This allows the fingerprint module to switch back to the fixed exposure mode and acquire fingerprint images according to the calibrated fixed exposure time.

[0108] This invention also provides an exposure time calibration device for a fingerprint module, referring to... Figure 3 , Figure 3 A schematic diagram of an exposure time calibration device for a fingerprint module is shown, as follows. Figure 3 As shown, the device includes:

[0109] The acquisition module is used to acquire an exposure time series, which includes multiple input exposure times. One input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode.

[0110] The determination module is used to determine the exposure time after this calibration based on multiple recorded exposure times in the exposure time series;

[0111] The update module is used to update the fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode to the exposure time after this calibration.

[0112] Optionally, the determining module includes:

[0113] The candidate exposure time determination submodule is used to obtain candidate exposure times based on the duration of each of the multiple recorded exposure times in the exposure time sequence;

[0114] The first determining submodule is used to determine the exposure time after this calibration based on the candidate exposure times.

[0115] Optionally, the first determining submodule includes:

[0116] The historical exposure time acquisition unit is used to acquire the exposure time after one or more historical calibrations when the current calibration is not the first calibration.

[0117] The first determining unit is used to determine the exposure time after the current calibration based on the candidate exposure time and the exposure time after one or more historical calibrations.

[0118] Optionally, the first determining submodule includes:

[0119] The second determining unit is used to determine the candidate exposure time as the exposure time after this calibration when this calibration is the first calibration.

[0120] Optionally, the candidate exposure time determination submodule includes:

[0121] The first acquisition unit is used to acquire the first N recorded exposure times from the exposure time sequence in descending order of duration.

[0122] The ratio determination unit is used to determine one of the first N recorded exposure times as the candidate exposure time based on the ratio between each recorded exposure time and the next adjacent recorded exposure time.

[0123] Optionally, the ratio determination unit includes:

[0124] The first ratio determination subunit is used to determine the ratio between each recorded exposure time and the next adjacent recorded exposure time in descending order of duration for the first N recorded exposure times.

[0125] The second ratio determination subunit is used to determine the candidate exposure time as the first of the first N recorded exposure times whose ratio with the next adjacent recorded exposure time satisfies the target condition.

[0126] The third ratio determination subunit is used to determine the smallest recording exposure time among the first N recording exposure times as the candidate exposure time, provided that there is no ratio between the first N recording exposure times and the next adjacent recording exposure time that satisfies the target condition.

[0127] Optionally, the target condition is that the ratio between two adjacent recorded exposure times is less than a target threshold.

[0128] Optionally, the exposure mode of the fingerprint module is set to a fixed exposure mode by default; the device further includes:

[0129] The detection module is used to detect whether an exposure time calibration request for the fingerprint module has been received;

[0130] The acquisition module includes:

[0131] The switching submodule is used to switch the exposure mode of the fingerprint module from a fixed exposure mode to an automatic exposure mode when an exposure time calibration request for the fingerprint module is detected.

[0132] The exposure time series acquisition submodule is used to perform a fingerprint enrollment on a finger pressing the fingerprint recognition area of ​​the screen through the fingerprint module, and obtain an enrollment exposure time. Multiple enrollment exposure times constitute the exposure time series.

[0133] This invention also provides an electronic device, with reference to... Figure 4 , Figure 4 This is a schematic diagram of the electronic device proposed in an embodiment of this application. Figure 4 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 communication. The memory 110 stores a computer program, which can run on the processor 120 to implement the steps in the fingerprint module exposure time calibration method disclosed in the embodiments of the present invention.

[0134] This application also provides a computer-readable storage medium storing a computer program / instructions thereon, which, when executed by a processor, implements the steps in the fingerprint module exposure time calibration method disclosed in this embodiment of the invention.

[0135] This invention also provides a computer program product, which, when run on an electronic device, enables the processor to implement the steps of a fingerprint module detection method disclosed in this invention.

[0136] 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.

[0137] Embodiments of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods, apparatuses, electronic devices, 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 and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0138] 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.

[0139] 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.

[0140] 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 present invention.

[0141] 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.

[0142] The above provides a detailed description of the fingerprint module exposure time calibration method, apparatus, and product provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is 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. An exposure time calibration method of a fingerprint module, characterized in that, include: Obtain an exposure time series, which includes multiple input exposure times. One input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode. Based on the multiple recorded exposure times in the exposure time series, determine the exposure time after this calibration; The fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode is updated to the exposure time after this calibration. Based on multiple recorded exposure times in the exposure time series, the exposure time after this calibration is determined, including: Candidate exposure times are obtained based on the duration of each of the multiple recorded exposure times in the exposure time series; Based on the candidate exposure times, determine the exposure time after this calibration.

2. The exposure time calibration method of claim 1, wherein, Based on the candidate exposure times, determine the exposure time after this calibration, including: If this calibration is not the first calibration, obtain the exposure time after one or more historical calibrations; The exposure time after this calibration is determined based on the candidate exposure time and the exposure time after one or more historical calibrations.

3. The exposure time calibration method according to claim 1, characterized in that, Based on the candidate exposure times, determine the exposure time after this calibration, including: In the case that this calibration is the first calibration, the candidate exposure time will be determined as the exposure time after this calibration.

4. The exposure time calibration method according to any one of claims 1-3, characterized in that, Based on the duration of each of the multiple recorded exposure times in the exposure time series, candidate exposure times are obtained, including: According to the order of duration from longest to shortest, the first N recorded exposure times are obtained from the exposure time series; Based on the ratio between each of the first N recorded exposure times and the next adjacent recorded exposure time, one of the first N recorded exposure times is determined as the candidate exposure time.

5. The exposure time calibration method according to claim 4, characterized in that, One of the first N recorded exposure times is determined as the candidate exposure time, including: For the first N recorded exposure times, determine the ratio between each recorded exposure time and the next adjacent recorded exposure time in descending order of duration; The candidate exposure time is determined as the one in which the ratio between the first of the first N recorded exposure times and the next adjacent recorded exposure time satisfies the target condition. If, among the first N recorded exposure times, there is no ratio between the time record time and the next adjacent recorded exposure time that satisfies the target condition, the smallest recorded exposure time among the first N recorded exposure times is determined as the candidate exposure time.

6. The exposure time calibration method according to claim 5, characterized in that, The target condition is that the ratio between two adjacent recorded exposure times is less than a target threshold.

7. The exposure time calibration method according to any one of claims 1-3, characterized in that, The fingerprint module's exposure mode is set to a fixed exposure mode by default; it also includes: Detect whether an exposure time calibration request for the fingerprint module has been received; Obtain the exposure time series, including: Upon detecting an exposure time calibration request for the fingerprint module, the exposure mode of the fingerprint module is switched from fixed exposure mode to automatic exposure mode; The fingerprint module performs a fingerprint registration once by pressing a finger on the fingerprint recognition area of ​​the screen, and obtains a registration exposure time. Multiple registration exposure times constitute the exposure time sequence.

8. An exposure time calibration device for a fingerprint module, characterized in that, include: The acquisition module is used to acquire an exposure time series, which includes multiple input exposure times. One input exposure time is the exposure time used by the fingerprint module to complete one fingerprint input in automatic exposure mode. The determination module is used to determine the exposure time after this calibration based on multiple recorded exposure times in the exposure time series; The update module is used to update the fixed exposure time used by the fingerprint module for fingerprint acquisition in fixed exposure mode to the exposure time after this calibration. The determining module includes: The candidate exposure time determination submodule is used to obtain candidate exposure times based on the duration of each of the multiple recorded exposure times in the exposure time sequence; The first determining submodule is used to determine the exposure time after this calibration based on the candidate exposure times.

9. 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 steps in the exposure time calibration method for the fingerprint module according to any one of claims 1-7.

10. A computer-readable storage medium having a computer program / instructions stored thereon, characterized in that, When the computer program / instruction is executed by the processor, it implements the steps in the exposure time calibration method for the fingerprint module according to any one of claims 1-7.

11. A computer program product, characterized in that, When the computer program product is run on an electronic device, it causes the processor to execute the steps in the exposure time calibration method of the fingerprint module as described in any one of claims 1-7.

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