Patent ID: 11884214
Assignee: BEIJING BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC B  H  G | IPC B  G  H

Claim 5:
6. The method according to claim 1, wherein the target feature model comprises a standard facial feature model, the standard facial feature model comprising a plurality of feature points and three-dimensional coordinates of each of the feature points; and
prior to acquiring the facial posture information of the driver of the vehicle in the camera coordinate system by the any one driver monitoring assembly of the at least one driver monitoring assembly, the method further comprises:
establishing the world coordinate system;
acquiring a target image of the standard facial feature model by the any one driver monitoring assembly;
determining planar coordinates of the plurality of feature points in the standard facial feature model based on the target image;
acquiring an internal parameter matrix and a distortion coefficient of the any one driver monitoring assembly by calibrating the any one driver monitoring assembly;
acquiring the second conversion relationship by solving a perspective-n-point problem based on the internal parameter matrix, the distortion coefficient, the three-dimensional coordinates, and the planar coordinates;
acquiring a rotation matrix and a translation vector between the standard facial feature model and the world coordinate system;
determining the third conversion relationship based on the rotation matrix and the translation vector; and

determining the first conversion relationship based on the third conversion relationship and the second conversion relationship.