Method for providing a code pattern
In accordance with a first aspect of the present disclosure, a method for providing a code pattern which is readable by a sensor is conceived, the method comprising: defining a plurality of coding positions as a subset of positions in a two-dimensional matrix; including in said subset a plurality of positions which are diagonally adjacent to each other; selectively creating coding marks, such as coding dots, at the coding positions. In accordance with a second aspect of the present disclosure, a corresponding code pattern is provided.
1. A method for providing a code pattern which is readable by a sensor, comprising:
defining a plurality of coding positions as a subset of positions in a two-dimensional matrix;
including in said subset a plurality of coding positions which are diagonally adjacent to each other and a plurality of coding positions that are not adjacent to other coding positions;
removing one coding position of a pair of coding positions in the subset that are vertically adjacent to each other;
removing one coding position of a pair of coding positions in the subset that are horizontally adjacent to each other; and
selectively creating coding marks only at the diagonally adjacent coding positions and at the coding positions that are not adjacent vertically or horizontally to other coding positions.
2. The method of claim 1 , further comprising creating orientation marks at predefined orientation mark positions in the matrix.
3. The method of claim 2 , wherein the predefined orientation mark positions are positions in one or more corners of the matrix.
4. The method of claim 1 , further comprising logically grouping a predefined number of coding positions in one or more coding fields.
5. The method of claim 4 , wherein the predefined number of coding positions in each coding field is p−1, wherein p represents the base of a Galois field GF(p n ), and wherein n is the number of coding fields in the matrix.
6. The method of claim 4 , wherein at most one coding mark is created in each coding field.
7. The method of claim 4 , further comprising logically grouping a predefined number of coding positions in a check number field.
8. The method of claim 7 , wherein the predefined number of coding positions in the check number field is p, wherein p represents the base of a Galois field GF(p n ), and wherein n is the number of coding fields in the matrix.
9. The method of claim 7 , wherein the check number field is placed in the center of the matrix.
10. The method of claim 1 , wherein the matrix is provided on a substrate, and wherein the coding marks are created by creating cavities in said substrate.
11. The method of claim 1 , wherein the matrix is provided on a substrate, and wherein the coding marks are created by punching holes in said substrate.
12. The method of claim 10 , wherein the substrate comprises an aluminum tape or an aluminum sheet.
13. The method of claim 1 , wherein the sensor is an optical fingerprint sensor, an acoustic fingerprint sensor, or a capacitive fingerprint sensor.
14. The method of claim 1 , wherein the code pattern represents a personal unlock key for unlocking a fingerprint template enrolment process.
15. A code pattern which is readable by a sensor, the code pattern comprising:
selectively created coding marks at a plurality of coding positions;
wherein the plurality of coding positions is defined as a subset of positions in a two-dimensional matrix;
and wherein said subset of positions only includes a plurality of coding positions which are diagonally adjacent to each other and a plurality of coding positions that are not adjacent to other coding positions either vertically or horizontally.