TW202004554A - Fingerprint enrollment method and electronic device for the same - Google Patents

Abstract

The present invention relates to a fingerprint enrollment method and an electronic device for the same. The fingerprint sensor detects the fingerprint to generate the fingerprint images. The processing unit determines whether the amount of times the finger touches the fingerprint sensor has reached N times, or whether the qualified fingerprint images have reached M sheets. When any of the conditions is satisfied, the sensing fingerprint is stopped. The fingerprint images is used to generate fingerprint enrollment information to complete the fingerprint enrollment process. With the present invention, the user can complete the fingerprint enrollment process regardless of whether the user uses the spiral enrollment or press enrollment.

Description

Fingerprint registration method and electronic device

The invention relates to the registration of biometrics, especially to the registration method of fingerprints.

Fingerprint recognition is commonly used in electronic devices nowadays. As one of the user identification technologies, the user must register the fingerprint of at least one finger in the electronic device in advance. When identity recognition is required (such as unlocking an electronic device, opening a specific application, using a specific function, etc.), the electronic device senses the user's fingerprint and compares it with the pre-registered fingerprint to identify the user's identity.

According to the existing fingerprint registration method, the user can only use a specific method for fingerprint input. A common fingerprint registration method is press registration, which requires the user to press the fingerprint sensor multiple times with different parts of the finger to obtain multiple fingerprint images as fingerprint registration information. Each press generates a fingerprint image. It usually takes a long time to register using push registration, but it is still a common and commonly used fingerprint registration method.

The present invention proposes a fingerprint registration method that can allow users to perform fingerprint registration in different ways.

In order to achieve the above-mentioned object of the invention, the technical means adopted by the present invention is to provide a fingerprint registration method which senses the fingerprint of a finger through a fingerprint sensor to generate a fingerprint image. The method includes the following steps: a. Obtain M qualified fingerprint images; b. Determine whether the finger touches the fingerprint sensor N times; and c. After performing steps a and b, when the judgment of step a or b is yes, the fingerprint sensing The device stops sensing fingerprints, where M and N are positive integers greater than 1.

The invention also provides an electronic device, which includes: a fingerprint sensor for sensing the fingerprint of a finger to obtain a fingerprint image; a processing unit, the processing unit is coupled to the fingerprint sensor, the processing The unit performs the following steps: a. determine whether M qualified fingerprint images are obtained; b. determine whether the finger touches the fingerprint sensor N times; and c. after performing steps a and b, when step a or b Determines that the fingerprint sensor stops sensing fingerprints, where M and N are positive integers greater than 1.

The advantage of the present invention is that, by judging two different fingerprint registration completion conditions, the user can complete the fingerprint registration procedure regardless of spiral registration or press registration, which effectively improves the convenience of use.

Referring to FIG. 1, according to an embodiment of the present invention, an electronic device includes a fingerprint sensor 10, a display 20, a processing unit 30, and a storage medium 40. The storage medium 40 stores the processing unit 30 in progress The code required for the fingerprint registration process. The processing unit 30 is coupled to the fingerprint sensor 10, the display 20 and the storage medium 40. The fingerprint sensor 10 is used to sense the fingerprint of a finger. The size of the fingerprint sensor 10 is smaller than the finger. For example, the size of the fingerprint sensor 10 is currently 6mm*6mm to 12mm*12mm, and the size of the finger is about 20mm*20mm. The fingerprint sensor 10 may be an optical type or a capacitive type, which can be applied to the present invention.

FIG. 2A provides an embodiment of the fingerprint registration method of the present invention. Step S10 is a procedure to start fingerprint registration. During the fingerprint registration process, the user inputs a finger's fingerprint through the fingerprint sensor 10. The fingerprint sensor 10 senses the finger to obtain a plurality of fingerprint images, and transmits the plurality of fingerprint images to the processing unit 30. In step S20, the processing unit 30 determines whether M qualified fingerprint images are obtained. Qualified fingerprint images are used to generate fingerprint registration information, and unqualified fingerprint images are discarded. If the determination in step S20 is YES, step S40 is performed to cause the fingerprint sensor 10 to stop sensing the fingerprint. If the judgment of step S20 is NO. Then, step S20 is continued. In step S30, the processing unit 30 determines whether the number of times the user's finger touches the fingerprint sensor 10 reaches N times. If the determination in step S30 is YES, step S40 is performed. If the determination in step S30 is NO, step S30 is continuously executed. The above M and N are positive integers greater than 1, in one embodiment, M is greater than or equal to N.

After step S40, step S50 is performed, and the processing unit 30 generates fingerprint registration information according to the qualified fingerprint image. In an embodiment, after a qualified fingerprint image is processed by the algorithm of the processing unit 30, a piece of fingerprint registration information is generated. Based on the M qualified fingerprint images, the processing unit 30 generates M pen fingerprint registration information.

When the judgment in step S20 or S30 is yes, it means that fingerprint registration has been completed, so the fingerprint sensor 10 can be stopped from sensing the fingerprint. The processing unit 30 generates fingerprint registration information according to the fingerprint image that has been judged to be qualified.

In one embodiment, when step S10 is performed, or before step S10, an instruction may be provided to prompt the user to move the finger on the fingerprint sensor 10 in a spiral path when performing fingerprint registration. In one embodiment, the indication is a visually visible indication. When the electronic device performs the fingerprint registration operation, the processing unit 30 provides the instruction to the display 20, and causes the display 20 to display the instruction. The display method may have the following different implementations, but not limited thereto. In other embodiments, the instruction may also be a voice instruction.

In the embodiment shown in FIG. 3, the instruction is a set of characters 70 displayed on the display 20. The content of the set of characters 70 may be, for example, "Please move your finger in a spiral manner on the fingerprint sensor".

Please refer to FIG. 4. In one embodiment, the indicator is a spiral curve 71, which is displayed on the display 20 to prompt the user to move the finger according to the spiral curve 71. In one embodiment, the fingerprint sensor 100 may be displayed on the display 20 to indicate the location 100.

In other embodiments, the indication includes a spiral curve and a direction sign, the direction sign is used to indicate whether the direction of the spiral curve is from inside to outside or from outside to inside to remind the user to move the finger direction. For example, the indicator 720 shown in FIG. 5 includes a spiral curve 72 and a direction mark 724. The direction mark 724 is an arrow located at one end of the spiral curve 72. The direction mark 724 is used to indicate that the inner end 721 of the spiral curve 72 is the starting point, and the outer end point 722 of the spiral curve 72 is the ending point. Or, for example, the indication 730 shown in FIG. 6 includes a spiral curve 73 and a direction mark 734. The direction mark 734 is located at one end of the spiral curve 73. The direction sign 734 is an arrow, which indicates that the outer end point 732 of the spiral curve 73 is the starting point, and the inner end point 731 of the spiral curve 73 is the ending point.

In FIG. 5, the direction indicating 720 is clockwise. In the embodiment shown in FIG. 7, the direction of the indicator 740 is counterclockwise.

In other embodiments, the indication is an animation. Taking the spiral curve 71 shown in FIG. 4 as an example, the method for displaying the indication on the display 20 is to display the spiral curve 71 from inside to outside, or to display the spiral curve 71 from outside to inside. As shown in FIGS. 8A to 8C, when the spiral curve 71 is displayed, the spiral curve 71 is displayed from the inside out. For example, first, the first line segment 711 is displayed as shown in FIG. 8A, and then as shown in FIG. 8B The first line segment 711 and the second line segment 712, and then the first line segment 711, the second line segment 712, and the third line segment 713 are shown in FIG. 8C, and finally the complete spiral curve 71 is shown in FIG. 7.

For another embodiment, please refer to FIG. 9A to FIG. 9C in conjunction with FIG. 4, when the display 20 displays the spiral curve 71, the spiral curve 71 is displayed from the outside to the inside. Four line segments 714, then the fourth line segment 714 and the fifth line segment 715 are shown in FIG. 9B, then the fourth line segment 714, the fifth line segment 715, and the sixth line segment 716 are shown in FIG. 9C, and finally the complete spiral is shown in FIG. 4状温度71。 The curve 71.

Since the size of the fingerprint sensor 10 is smaller than the finger, the fingerprint image is an image of a part of the complete fingerprint of the finger. If the user moves the finger on the fingerprint sensor 10 in a spiral path according to the above-mentioned instructions, the fingerprint sensor 10 performs multiple times on the finger during the movement of the finger on the fingerprint sensor 10 For sensing, multiple fingerprint images 60 are obtained as shown in FIG. 10. If the user takes a press registration, the user's finger needs to touch the fingerprint sensor 10 multiple times and leave the fingerprint sensor 10. Whenever the finger touches the fingerprint sensor 10, the fingerprint sensor 10 senses the finger 50 to obtain a fingerprint image. Therefore, when the user performs the press registration procedure, the fingerprint sensor 10 performs multiple sensing on the finger to obtain multiple fingerprint images 61 as shown in FIG. 11.

According to the method of the present invention, when the processing unit 30 determines that M effective fingerprint images are obtained or the number of times the finger touches the fingerprint sensor 10 reaches N times, the fingerprint sensor 10 stops sensing the fingerprint. If the user performs fingerprint registration by a finger moving spirally on the fingerprint sensor 10, the processing unit 30 will first determine that M valid fingerprint images have been obtained (ie, the determination in step S30 is YES) and end the registration process. When the user adopts the method of pressing registration, the processing unit 30 may first determine that the number of times the finger touches the fingerprint sensor 10 has reached N times, and then end the registration procedure. Therefore, for the user, no matter how the finger is used to input the fingerprint, the fingerprint registration process can be successfully completed. In other words, the method provided by the present invention is suitable for at least two fingerprint registration methods. The user can perform the fingerprint registration procedure according to his own habits or preferences. Therefore, the present invention can provide a better user experience.

FIG. 2B provides another embodiment of the present invention, in which a plurality of steps are included in addition to steps S30 and S20. After the procedure of fingerprint registration is started in step S10, step S31 is performed. Step S31 is to determine whether the finger touches the fingerprint sensor 10. In one embodiment, the fingerprint sensor 10 is a capacitive fingerprint sensor, which includes a sensing array with 80 X-direction sensing electrodes and 80 Y-direction sensing electrodes. According to the sensing amount of at least one sensing electrode (for example, two X-direction sensing electrodes or two Y-direction sensing electrodes), it can be determined whether a finger touches the fingerprint sensor 10. When a finger touches the fingerprint sensor 10, the potential of an input/output contact (I/O) of the fingerprint sensor 10 is pulled from a low voltage level to a high voltage level. The processing unit 30 can know that a finger is touching the fingerprint sensor 10 according to the potential of the input/output contact, and then instruct the fingerprint sensor 10 to perform fingerprint sensing to obtain a fingerprint image.

After it is determined in step S31 that no finger touches the fingerprint sensor 10, step S31 is performed again to continuously detect whether a finger touches the fingerprint sensor 10. When it is determined in step S31 that a finger touches the fingerprint sensor 10, step S11 and step S32 are performed respectively. In step S11, the processing unit 30 instructs the fingerprint sensor 10 to sense the user's finger to obtain a fingerprint image. The fingerprint image sensed by the fingerprint sensor 10 is transmitted to the processing unit 30 to proceed to step S21.

Step S32 is to determine whether the finger leaves the fingerprint sensor 10. In one embodiment, the processing unit 30 determines whether the finger leaves according to the image transmitted from the fingerprint sensor 10. For example, the image generated by the fingerprint sensor 10 includes 80×80 (ie, 6400) sensing values (or pixel values), and the processing unit 30 compares the sum of these 6400 sensing values with a threshold value. If the sum is lower than the threshold, it means that the finger has left the fingerprint sensor 10.

When it is determined in step S32 that the finger has not left the fingerprint sensor 10, it returns to step S31 to continue to detect whether the finger still contacts the fingerprint sensor 10. As can be seen from the flowchart of FIG. 2B, every time it is determined that the finger is touching the fingerprint sensor 10, the fingerprint sensor 10 senses the finger to capture the fingerprint image. Therefore, each time a finger touches the fingerprint sensor 10, the fingerprint sensor 10 will produce more than one fingerprint image. The longer the finger touches the fingerprint sensor 10, the more the fingerprint sensor 10 produces Fingerprint image. When it is determined in step S32 that the finger is away from the fingerprint sensor 10, step S33 is performed. In step S33, the processing unit 30 increments the number of times the finger touches the fingerprint sensor. Step S33 is to accumulate the number of times the fingerprint sensor 10 has been touched since the fingerprint program was started. In step S30, the processing unit 30 determines whether the number of times the finger touches the fingerprint sensor reaches N times based on the calculation result in step S33. If the determination in step S30 is YES, step S40 is performed. In step S40, the fingerprint sensor 10 stops sensing the fingerprint. In one embodiment, when the processing unit 30 determines that the finger touches the fingerprint sensor N times, it no longer instructs the fingerprint sensor 10 to sense the fingerprint, so that the fingerprint sensor 10 stops sensing the fingerprint. If the determination in step S30 is negative, then return to step S31 to continue to detect whether the finger touches the fingerprint sensor 10 again.

In step S21, the processing unit 30 determines whether the fingerprint image obtained in step S11 is qualified. When the fingerprint image is determined to be qualified, step S22 is performed to increase the number of qualified fingerprint images by one. When the fingerprint image is judged to be unqualified, step S23 is performed, the fingerprint image is discarded, and the process returns to step S31 to continue to determine whether the finger touches the fingerprint sensor 10. In the embodiment shown in FIG. 2B, step S21 includes steps S211 and S212. Step S211 is to determine whether there is a difference between the previous fingerprint image of the currently obtained fingerprint image. An embodiment of step S211 includes the operation of subtracting a fingerprint image from its previous fingerprint image. For example, the size of the fingerprint image is 80*80 pixels. The method to determine whether there is a difference between the fingerprint image of the Pth sheet and the previous sheet (ie, the P-1st sheet) is to convert the two fingerprint images first, and express the value of each pixel with a value of 0 to 256, for example Pixel values. Next, the pixel values of the two fingerprint images are subtracted to obtain 6400 (80*80) difference values, and the sum of these 6400 difference values is calculated. The sum of the difference values is used to compare with a sum threshold value. When the sum of the difference values is greater than the sum threshold value, it is judged that there are differences between the two fingerprint images before and after. In other embodiments, the sum of the above differences may be divided by 6400 to obtain a difference average, and the difference average may be compared with an average threshold value. When the difference is greater than the average threshold value on average, it is determined that the two fingerprint images before and after there are differences.

If the judgment result of step S211 is yes, then proceed to step S212. If the judgment result in step S211 is no, then proceed to step S23, discard the fingerprint image, and return to step S31, continue to judge whether the finger touches the fingerprint sensor 10. In the process of fingerprint registration, it is desirable to obtain fingerprints in all areas of the finger as much as possible. With step S211, it is possible to avoid storing multiple identical fingerprint images. If there is a difference between a fingerprint image and the previous fingerprint image, it means that the two fingerprint images are different regions corresponding to the finger.

Step S212 is to determine whether the fingerprint density D of the fingerprint image falls within an allowable range. The fingerprint density D of the fingerprint image 60 can be calculated in various ways. In some embodiments, the number of ridges covered by two diagonal lines (or more straight lines) of the fingerprint image, the valley (Valley) number, or the number of times the peaks and valleys alternate as fingerprint density. The allowable range of the fingerprint density D can be determined by the fingerprint density D1 of the first fingerprint image obtained by the fingerprint sensor 10 sensing the finger. For example, if the fingerprint density D1 is 10, the allowable range is between a predetermined range of 10 (for example, 30% up and down), which is 7 to 13. Generally speaking, the rapid movement of the finger on the fingerprint sensor 10 is easy to produce a deformed fingerprint image, which cannot be used to generate fingerprint registration information. Since the fingerprint density of this deformed fingerprint image is low, by determining whether the density of the fingerprint image falls within an allowable range, the deformed fingerprint image can be excluded.

When the judgment in step S212 is yes, it means that the fingerprint image is qualified. Next, step S22 is performed. If the judgment result in step S212 is NO, proceed to step S23 to discard the fingerprint image, and return to step S31 to continue to determine whether the finger touches the fingerprint sensor 10. Step S22 is to accumulate the number of qualified fingerprint images. Step S20 determines whether M qualified fingerprint images have been obtained based on the calculation result of step S22. In an embodiment, the processing unit 30 compares the cumulative number of qualified fingerprint images with a preset value M to determine whether the number of qualified fingerprint images reaches the preset value M. When the determination in step S20 is YES, step S40 is performed. When the determination in step S20 is NO, it returns to step S31 and continues to determine whether the finger touches the fingerprint sensor.

Step S21 in FIG. 2B is only an embodiment, and is not intended to limit the present invention. In other embodiments (as shown in FIG. 2C), the order of steps S211 and S212 can be reversed. Alternatively, more judgment conditions may be added in step S21. Alternatively, step S21 may also reduce the judgment condition. For example, step S21 includes only one of steps S211 and S212.

In the description of the above embodiment, the fingerprint sensor 31 is mainly used to sense the fingerprint and determine whether there is a finger contact. Other steps are performed by the processing unit 30, corresponding to the program codes of each step of FIG. 2B or FIG. 2C It may be stored in the storage medium 40, and the processing unit 30 implements each step by executing the program code in the storage medium 40. However, the present invention is not intended to limit the hardware that implements each step. In other embodiments, if the fingerprint sensor 30 has a powerful microprocessor, all the steps in FIGS. 2A to 2C or some of the steps that require calculation may also be performed by the fingerprint sensor 10 .

The above is only an embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field of the art, Within the scope of not departing from the technical solution of the present invention, when the technical contents disclosed above can be used to make some modifications or modifications to equivalent embodiments of equivalent changes, but any content that does not depart from the technical solution of the present invention, based on the technical essence of the present invention Any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the technical solution of the present invention.

100‧‧‧Fingerprint sensor schematic position 10‧‧‧Fingerprint sensor 20‧‧‧Display 30‧‧‧Processing unit 40‧‧‧Storage medium 60, 61‧‧‧Fingerprint image 70‧‧‧Text 720 , 730, 740‧‧‧ instructions 71, 72, 73‧‧‧ spiral curve 711‧‧‧ first line segment 712‧‧‧ second line segment 713‧‧‧ third line segment 714‧‧‧ fourth line segment 715‧ ‧‧Fifth line segment 716‧‧‧Sixth line segment 721,731‧‧‧‧Internal end point 722,732‧‧‧Outer end point 724,734‧‧‧Direction mark

FIG. 1 is a block diagram of an electronic device of the present invention. 2A is a flowchart of an embodiment of the invention. 2B is a flowchart of another embodiment of the present invention. 2C is a flowchart of another embodiment of the present invention. FIG. 3 is a schematic diagram of the first embodiment of the indication of the present invention. 4 is a schematic diagram of a second embodiment of the indication of the present invention. 5 is a schematic diagram of a third embodiment of the indication of the present invention. 6 is a schematic diagram of a fourth embodiment of the indication of the present invention. 7 is a schematic diagram of a fifth embodiment of the indication of the present invention. 8A to 8C are schematic diagrams of the first embodiment of the present invention displaying an indication. 9A to 9C are schematic diagrams of a second embodiment of the present invention displaying an indication. 10 is a schematic diagram of a fingerprint image obtained by finger registration in a spiral manner. FIG. 11 is a schematic diagram of a fingerprint image obtained by finger registration.

Claims (27)

A fingerprint registration method, which senses a finger's fingerprint through a fingerprint sensor to generate a fingerprint image, the method includes the following steps: a. determine whether to obtain M qualified fingerprint images; b. determine the finger contact Whether the number of times of the fingerprint sensor reaches N times; and c. after performing steps a and b, when the judgment of step a or b is yes, the fingerprint sensor stops sensing fingerprints, wherein the M and N are greater than 1 Positive integer. The fingerprint registration method according to claim 1, further comprising: d. judging whether the fingerprint image generated by the fingerprint sensor is qualified; e. accumulating the number of qualified fingerprint images; and f. accumulating the The number of times the finger touches the fingerprint sensor; wherein, the calculation result of step e is used to make the judgment of step a. If the judgment result of step a is no, then repeat step d and step e, the step The calculation result of f is used for the judgment of step b. The fingerprint registration method according to claim 2, wherein in step d, the step of judging that the fingerprint image is qualified includes: d1. judging that there is a difference between the fingerprint image and the previous fingerprint image. The fingerprint registration method according to claim 2 or 3, wherein in step d, the step of judging that the fingerprint image is qualified includes: d2. judging that the fingerprint density of the fingerprint image falls within an allowable range. The fingerprint registration method according to claim 2, wherein the step f includes counting once when the finger touches the fingerprint sensor and leaves the fingerprint sensor. The fingerprint registration method according to claim 1, wherein M is greater than or equal to N. The fingerprint registration method according to claim 1, further comprising the following steps: providing a first indication for prompting the user to move the finger on the fingerprint sensor in a spiral path. The fingerprint registration method according to claim 7, wherein the first instruction includes a set of characters. The fingerprint registration method according to claim 7, wherein the first indication includes a spiral curve. The fingerprint registration method according to claim 9, wherein the first indication further includes a direction mark, the direction mark is used to indicate whether the direction of the spiral curve is from inside to outside or from outside to inside to remind the user The direction to move the finger. The fingerprint registration method according to claim 9, wherein the method of displaying the first indication is to display the spiral curve from inside to outside, or to display the spiral curve from outside to inside. The fingerprint registration method according to claim 1, wherein when the finger is moved on the fingerprint sensor in a spiral path to perform the fingerprint registration, the result judged as yes in step a is obtained first. The fingerprint registration method according to claim 1, wherein each time the finger touches the fingerprint sensor, the fingerprint sensor produces more than one fingerprint image. An electronic device including: a fingerprint sensor for sensing a fingerprint of a finger to obtain a fingerprint image; and a processing unit coupled with the fingerprint sensor, the processing unit performs the following Steps: a. Determine whether M qualified fingerprint images are obtained; b. Determine whether the finger touches the fingerprint sensor N times; and c. After performing steps a and b, when step a or b It is judged as yes, the fingerprint sensor stops sensing fingerprints, wherein the M and N are positive integers greater than 1. The electronic device according to claim 14, wherein the processing unit further includes the following steps: d. determine whether the fingerprint image generated by the fingerprint sensor is qualified; e. accumulate the number of qualified fingerprint images; And f. accumulate the number of times the finger touches the fingerprint sensor; wherein, the calculation result of step e is used to make the judgment of step a, if the judgment result of step a is no, then repeat step d and Step e, the calculation result of step f, is used to make the judgment of step b. The electronic device according to claim 14, wherein in step d performed by the processing unit, the step of judging that the fingerprint image is qualified includes: d1. judging that there is a difference between the fingerprint image and the previous fingerprint image . The electronic device according to claim 15 or 16, wherein the step of the processing unit judging that the fingerprint image is qualified in step d includes: d2. It is judged that the fingerprint density of the fingerprint image falls within an allowable range. The electronic device according to claim 15, wherein the step f performed by the processing unit includes a count of 1 when the finger touches the fingerprint sensor and leaves the fingerprint sensor. The electronic device according to claim 14, wherein M is greater than or equal to N. As in the electronic device according to claim 14, the processing unit further performs the following steps: providing a first indication for prompting the user to move the finger on the fingerprint sensor in a spiral path. The electronic device of claim 20, wherein the first instruction includes a set of text. The electronic device of claim 20, wherein the first indication includes a spiral curve. The electronic device according to claim 22, wherein the first indication further includes a direction sign, the direction sign is used to indicate whether the direction of the spiral curve is from inside to outside or from outside to inside to prompt the user to move The direction of the finger. The electronic device according to claim 22, wherein the method for the processing unit to display the first indication is to display the spiral curve from inside to outside, or to display the spiral curve from outside to inside. The electronic device according to any one of claims 20 to 23, further comprising a display coupled to the processing unit, the processing unit providing the instruction to the display, the display displaying the instruction. The electronic device according to claim 14, wherein when the finger is moved on the fingerprint sensor in a spiral path for the fingerprint registration, the processing unit first obtains the result judged as YES in step a. The electronic device according to claim 14, wherein the fingerprint sensor produces more than one fingerprint image every time the finger touches the fingerprint sensor.

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