Patent ID: 11920912
Assignee: SHIP AND OCEAN INDUSTRIES R&DCENTER
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 4:
5. An operating method of an automatic berthing image ranging system for vessels, comprising:
providing the automatic berthing image ranging system for vessels of claim 1;
obtaining an to-be-recognized image, wherein if the to-be-recognized image comprises the first pattern and the at least two second patterns, the electronic control unit defines the to-be-recognized image as the reference image, and if not, re-captures the to-be-recognized image via the image capturing device;
extracting a first pixel coordinate and at least two second pixel coordinates from the reference image; wherein the first pixel coordinate corresponds to position of center point of the first pattern and the at least two pixel coordinates correspond to positions of center points of each of the second pattern;
projecting the reference image onto the reference plane;
converting the first pixel coordinate to a first projection coordinate and the at least two second pixel coordinates to at least two second projection coordinates;
determining whether a number of the at least two second projection coordinates of the reference plane is greater than two;
wherein if the number of the at least two second projection coordinates of the reference plane is greater than two, the electronic control unit performs operations including:
calculating a plurality of the projection distances from one second projection coordinate in the at least two second projection coordinates to another second projection coordinate;
comparing values of the plurality of the projection distances; and dividing a minimum value of the plurality of projection distances by the predetermined distance to yield the corresponding calibration ratio;

wherein if the number of the at least two second projection coordinates of the reference plane is equal to two, the electronic control unit divides a projection distance between the two second projection coordinates by the predetermined distance to yield the corresponding calibration ratio;
calculating the reference distance between the first projection coordinate and each of the second projection coordinates respectively;
multiplying each one of the plurality of reference distances by the corresponding calibration ratio individually to yield the plurality of real distances;
analyzing the reference image to define a first reference line and a second reference line that intersect to form the acute angle;
performing trigonometry calculations on the predetermined distance and the plurality of real distances, and accordingly estimating the value of the acute angle; and
storing the value of the acute angle.