Spatial Resection for Solving Camera Exterior Orientation Parameters

When using spatial resection to solve camera exterior orientation parameters, we need to consider the following variables:

- x, y: control point image coordinates

- X, Y, Z: control point ground coordinates

- f: focal length

- X0, Y0, Z0, a, b, c: six exterior orientation parameters (position and attitude angles)

- x0, y0, -f: interior orientation elements (principal point coordinates)

- cha, chb, chc: correction values for exterior angular elements (used in iterative refinement)

- count: iteration counter (tracks convergence progress)

- R: rotation matrix (constructed from attitude angles a, b, c using Euler angles or rotation matrices)

- A: linearized partial derivative coefficient matrix (Jacobian matrix in the least-squares adjustment)

- L: constant term matrix (residuals between observed and computed coordinates)

- M0: exterior orientation parameters matrix (stores current parameter estimates)

- M1: exterior orientation correction parameters matrix (contains parameter adjustments computed in each iteration)

These variables form the essential components for implementing spatial resection to determine camera exterior orientation parameters, typically through an iterative least-squares solution that minimizes the differences between observed and projected image coordinates.