Patent ID: 11899918
Assignee: ANHUI HONGCHENG OPTO-ELECTRONICS CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 14:
15. The method according to claim 14, wherein the preset pattern further comprises a fourth preset pattern, and after judging whether at least one of the key angles is within the preset straight angle threshold range, the method further comprises:
under a condition that none of the key angles is within the preset straight angle threshold range, selecting, on each key track, a point with a maximum vertical distance to the key line segment corresponding to the key track in sequence as an auxiliary point, wherein the key track refers to a sliding track between two ends of the key line segment;
determining a fitted elliptical track according to the key points and the auxiliary points;
judging whether a sum of distances, each of which is between a respective point on the sliding track and the fitted elliptical track, satisfies a preset fitting threshold;
judging whether the distance between the first key point and the fifth key point is greater than the preset distance threshold under a condition that the sum of the distances satisfies the preset fitting threshold; and
determining that the sliding track satisfies a recognition condition of the fourth preset pattern under a condition that the distance between the first key point and the fifth key point is not greater than the preset distance threshold.