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CN-116012894-B - Side fingerprint input method, electronic equipment and computer readable storage medium

CN116012894BCN 116012894 BCN116012894 BCN 116012894BCN-116012894-B

Abstract

The invention provides a side fingerprint input method, electronic equipment and a computer readable storage medium, wherein the side fingerprint input method comprises the steps of initializing an n multiplied by n input matrix, inputting elements of an a row and a b column of the matrix as a matrix H ab , sequentially extracting characteristic template information of first to n fingerprint images, calculating a transformation matrix between any two fingerprint image characteristic template information, filling the transformation matrix into the matrix H ab when the transformation matrix can be calculated for the a fingerprint image and the b fingerprint image, filling the zero matrix into the matrix H ab when the transformation matrix can not be calculated, traversing the zero matrix in the input matrix, searching the transformation matrix H jl and the transformation matrix H lk for the zero matrix H jk , and replacing the zero matrix H jk by the product of the two. The feature information templates of mutually isolated fingerprint images can be reduced, and the association degree between the feature information templates of all fingerprint images is improved, so that the accuracy of fingerprint input and subsequent unlocking of users is improved.

Inventors

  • XU KEFENG
  • WU HANFENG

Assignees

  • 广州国同芯微电子有限公司

Dates

Publication Date
20260508
Application Date
20211019

Claims (14)

  1. 1. A side fingerprint entry method, comprising the steps of: Initializing an n multiplied by n input matrix, wherein the elements of the a row and the b column of the input matrix are matrix H ab ; sequentially extracting characteristic template information of the first fingerprint image to the nth fingerprint image, and calculating a transformation matrix between any two fingerprint image characteristic template information; For an a-th fingerprint image and a b-th fingerprint image, when a transformation matrix can be calculated, filling the transformation matrix into the matrix H ab , and when the transformation matrix cannot be calculated, filling a zero matrix into the matrix H ab ; Traversing the zero matrix in the entry matrix, for the zero matrix H jk , looking up the transformation matrix H jl and the transformation matrix H lk , and replacing the zero matrix H jk with the product of the transformation matrix H jl and the transformation matrix H lk .
  2. 2. The side fingerprint input method according to claim 1, wherein initializing an n x n input matrix, the elements of the a-th row and the b-th column of the input matrix being a matrix H ab , specifically comprises: Initializing an n multiplied by n input matrix, wherein the elements of the a row and the b column of the input matrix are the matrix H ab , and filling the identity matrix into the matrix positioned on the main diagonal of the input matrix.
  3. 3. The side fingerprint input method according to claim 2, wherein "extracting feature template information of the first to nth fingerprint images in sequence and calculating a transformation matrix between feature template information of any two fingerprint images" specifically includes: And sequentially extracting characteristic template information of the first fingerprint image to the nth fingerprint image, and sequentially calculating a transformation matrix of the characteristic template information between the xth fingerprint image and the first fingerprint image to the xth-1 fingerprint image after extracting the characteristic template information each time, wherein x is more than or equal to 2 and less than or equal to n.
  4. 4. A side fingerprint entry method according to claim 3, wherein "filling the transformation matrix into the entry matrix corresponding element when a transformation matrix can be calculated, and filling the zero matrix into the entry matrix corresponding element when a transformation matrix cannot be calculated" specifically comprises: For the x-th fingerprint image and the x-i fingerprint image, when a transformation matrix M x,x-i of the x-th fingerprint image and the x-i fingerprint image can be obtained through calculation, filling the transformation matrix M x,x-i and an inverse matrix M x-i,x of the transformation matrix M x,x-i into a position of an initial matrix H x,x-i and a position of a matrix H x-i,x respectively, and when the transformation matrices of the x-th fingerprint image and the x-i fingerprint image cannot be obtained through calculation, filling a zero matrix into a position of a matrix H x,x-i and a position of a matrix H x-i,x respectively, wherein i < x is more than or equal to 1.
  5. 5. A side fingerprint entry method according to claim 3, characterized in that "traversing the zero matrix in the entry matrix", for zero matrix H jk , finding transformation matrix H jl and transformation matrix H lk , and replacing the zero matrix H jk "with the product of the two, comprises in particular: And when the characteristic template information of the first fingerprint image to the nth fingerprint image is completely extracted, and the input matrix is completely filled, traversing a zero matrix in the input matrix, searching a transformation matrix H jl and a transformation matrix H lk for the zero matrix H jk , and replacing the zero matrix H jk by the product of the two matrices.
  6. 6. A side fingerprint entry method according to claim 3, characterized in that "traversing the zero matrix in the entry matrix", for zero matrix H jk , finding transformation matrix H jl and transformation matrix H lk , and replacing the zero matrix H jk "with the product of the two, comprises in particular: And traversing a zero matrix in the input matrix after extracting the characteristic template information of the first to n/2 fingerprint images and correspondingly filling the input matrix, searching a transformation matrix H jl and a transformation matrix H lk for the zero matrix H jk , and replacing the zero matrix H jk by the product of the two.
  7. 7. A side fingerprint entry method according to claim 5 or 6, further comprising the step of: for the zero matrix H jk , when the transformation matrix H jl and the transformation matrix H lk do not exist at the same time, the feature information templates of the j-th fingerprint image and the k-th fingerprint image are used as the isolated feature information templates.
  8. 8. The side fingerprint entry method of claim 1, further comprising the step of: After extracting the characteristic template information of the fingerprint image each time, comparing the characteristic template information with the characteristic template information of other fingerprint images, and when the repeatability of the characteristic template information of any fingerprint image with the characteristic template information of the fingerprint image is larger than a repeatability threshold, re-inputting the fingerprint image and re-extracting the characteristic template information.
  9. 9. The side fingerprint entry method of claim 5, wherein the feature template information includes key point information and descriptors corresponding to key points in the fingerprint image.
  10. 10. The side fingerprint entry method of claim 1, wherein the transformation matrix is an affine transformation matrix.
  11. 11. The side fingerprint entry method of claim 1, wherein the transformation matrix is a rigid body transformation matrix.
  12. 12. The side fingerprint entry method of claim 11, wherein the independent parameters of the rigid body transformation matrix are each provided with a deviation threshold.
  13. 13. An electronic device comprising a fingerprint sensor, a memory and a processor, the fingerprint sensor being arranged on a side of the electronic device, the memory storing a computer program operable on the processor, the processor executing the program to perform the steps of the side fingerprint entry method of any one of claims 1-12.
  14. 14. A computer readable storage medium, characterized in that a computer program is stored therein and which, when run, causes a device on which the computer storage medium is located to perform the steps of the side fingerprint entry method according to any one of claims 1-12.

Description

Side fingerprint input method, electronic equipment and computer readable storage medium Technical Field The invention relates to the field of fingerprint identification, in particular to a side fingerprint input method, electronic equipment and a computer readable storage medium. Background With the popularity of full-screen cell phones, fingerprint identification sensors are gradually shifted from capacitive to off-screen optical. However, due to the high optical cost, side fingerprints are another option for manufacturers to reduce cost and maintain aesthetics. The side fingerprint is that the size of the capacitive fingerprint sensor is the same as that of the power key of the mobile phone, and the capacitive fingerprint sensor is placed on one side of the mobile phone. The information collected by the narrow-side sensor is less in the width direction, the existing fingerprint characteristic input mode is simpler, the fingerprint sensor collects fingerprint images and extracts characteristic information after being pressed by a finger for a single time. The finger continues to press, the fingerprint sensor collects fingerprint images, extracts characteristic information and compares the characteristic information with the last information, if the repeated area is large, the registration is returned to fail, otherwise, the registration is successful. When the number of the feature templates reaches the maximum limit, registration is ended. When the simple registration mode is used for a side fingerprint sensor, each template is easy to isolate and cannot form a whole, so that feature information input by the whole is not associated, and the template can only be used as a single feature to be authenticated with the currently acquired template during authentication, and the authentication is failed due to less information on the narrow side. Moreover, when the finger rotates for authentication, the finger is nearly vertical to the input direction, a plurality of templates in the template library are nearly vertical to the currently authenticated templates, and when the fingerprint sensor is narrower, the overlapping area is smaller, and under the condition of small-area overlapping, no matter how many times of templates are input, the unlocking effect is poorer. Disclosure of Invention The invention aims to provide a side fingerprint input method, electronic equipment and a computer readable storage medium. The invention provides a side fingerprint input method which is characterized by comprising the following steps: Initializing an n multiplied by n input matrix, wherein the elements of the a row and the b column of the input matrix are matrix H ab; sequentially extracting characteristic template information of the first fingerprint image to the nth fingerprint image, and calculating a transformation matrix between any two fingerprint image characteristic template information; For an a-th fingerprint image and a b-th fingerprint image, when a transformation matrix can be calculated, filling the transformation matrix into the matrix H ab, and when the transformation matrix cannot be calculated, filling a zero matrix into the matrix H ab; Traversing the zero matrix in the entry matrix, for the zero matrix H jk, searching the transformation matrix H jl and the transformation matrix H lk, and replacing the zero matrix H jk by the product of the two. As a further improvement of the present invention, "initializing an n×n entry matrix whose elements of row a and column b are matrix H ab" specifically includes: Initializing an n multiplied by n input matrix, wherein the elements of the a row and the b column of the input matrix are the matrix H ab, and filling the identity matrix into the matrix positioned on the main diagonal of the input matrix. As a further improvement of the present invention, "extracting feature template information of first to nth fingerprint images in sequence, and calculating a transformation matrix between feature template information of any two fingerprint images" specifically includes: feature template information of the first to nth fingerprint images is sequentially extracted, and after feature template information is extracted each time, a transformation matrix of feature template information between the (x is more than or equal to 2 and less than or equal to n) th fingerprint image and the first to (x-1) th fingerprint images is sequentially calculated. As a further improvement of the present invention, "filling the transformation matrix into the corresponding element of the input matrix when the transformation matrix can be calculated, and filling the zero matrix into the corresponding element of the input matrix when the transformation matrix cannot be calculated" specifically includes: for the x-th fingerprint image and the x-i (1 is less than or equal to i < x) fingerprint image, when a transformation matrix M x,x-i of the x-th fingerprint image and the x-i (1 is less than or