lambdatwist

Re-implementation of Lambda Twist P3P solver from the paper

M. Persson, K. Nordberg, Lambda Twist: An Accurate Fast Robust Perspective Three Point (P3P) Solver, ECCV 2018

The original implementation from the authors can be found here. The main difference in this implementation is that it uses Eigen and that it solves the cubic with a closed form solution. In our experiments this implementation has similar accuracy and speed as the original code.

The interface for the solver is (see p3p.h)

int p3p(const std::vector<Eigen::Vector3d> &x,
        const std::vector<Eigen::Vector3d> &X,
        std::vector<CameraPose> *output);

where the camera is modeled as

struct CameraPose {
      Eigen::Matrix3d R;
      Eigen::Vector3d t;
};

Note: The solver assumes that the vectors in x are normalized.

vlarsson/lambdatwist

lambdatwist