imagePoints
imagePoints is a term used in computer vision to denote a set of two-dimensional points in an image that correspond to a set of known three-dimensional points from a scene or object. In calibration and 3D reconstruction workflows, objectPoints are the 3D coordinates in a chosen coordinate system, and imagePoints are the projected 2D coordinates in the image plane obtained by projecting objectPoints using the camera intrinsics and extrinsics. In OpenCV and similar libraries, imagePoints are typically stored as a vector of 2D points (for example, std::vector<cv::Point2f> or a Mat with size N x 1 x 2). They are used as inputs or outputs for functions such as calibrateCamera, stereoCalibrate, and solvePnP. For example, during camera calibration, one provides a set of objectPoints and the corresponding imagePoints for multiple views; the function estimates the camera matrix and distortion coefficients that map between objectPoints and imagePoints.
imagePoints are usually measured in pixel coordinates (u, v) with the origin at the image's top-left corner,