Patent ID: 11880983
Assignee: LOGITECH EUROPE S.A.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 9:
10. The method of claim 9, wherein the calibration process further comprises:
performing a predefined perspective correction process, comprising:
correcting perspective distortion of the first image, the first image having a visible frame;

performing a first corner detection process, comprising:
detecting a location of a first corner of the surface in the first image;

performing a flipping process, comprising:
rotating the first image;

performing a second corner detection process, comprising:
detecting a location of a second corner of the surface in the first image;

performing the flipping process, comprising:
rotate the first image;

performing a third corner detection process, comprising:
detecting a location of a third corner of the surface in the first image;

performing the flipping process, comprising:
rotating the first image of the surface;

performing a fourth corner detection process, to detect a location of a fourth corner of the surface in the first image;
performing a false detection filtering process, comprising:
rejecting any of the detected locations of the first, second, third, and fourth corners of the surface outside of the visible frame;

performing a corner post process, comprising:
determining size and shape of an initial canvas image;

performing a fine turning process, to accurately determine a location of a center of the corners; and
performing a corner transformation process, comprising:
transform the determined locations of the corners to coordinates of the initial canvas image.