title: Initial camera intrinsic and extrinsic matrix and 3D point coordinates for Bundle Adjustment
body: <p>I want to reconstruct 3d scene using multi rgb cameras. The input data has no camera calibration information so I want to use bundle adjustment algorithm (Ceres-solver) to estimate the calibration information.</p>
  
  <p>Now I have already obtained pair-wise matched feature points but I find that the algorithm in bundle adjustment algorithm (Ceres-solver) also need initial camera intrinsic and extrinsic matrix and 3d point coordinates as input. However, I do not have this information and I do not know how to generate an initial guess, either. </p>
  
  <p>What should I do to generate the initial camera intrinsic and extrinsic matrix and 3d point coordinates?</p>
  
  <p>Thanks very much!</p>