Estimates best global motion between two 2D point clouds robustly (using RANSAC method)

M = cv.estimateGlobalMotionRansac(points0, points1)
[M,rmse,ninliers] = cv.estimateGlobalMotionRansac(points0, points1)
[...] = cv.estimateGlobalMotionRansac(..., 'OptionName',optionValue, ...)

Input

• points0 Source set of 2D points of type single, stored in numeric array (Nx2/Nx1x2/1xNx2) or cell-array of 2-element vectors {[x,y], [x,y], ...}.
• points1 Destination set of 2D points of type single, of same format as points0.

Output

• M 3x3 2D transformation matrix of type single.
• rmse Final root-mean-square error.
• ninliers Final number of inliers.

Options

• MotionModel Motion model between two point clouds. One of:

  • Translation
  • TranslationAndScale
  • Rotation
  • Rigid
  • Similarity
  • Affine (default)

• RansacParams RANSAC method parameters. A struct with the following fields:

  • Size Subset size.
  • Thresh Maximum re-projection error value to classify as inlier.
  • Eps Maximum ratio of incorrect correspondences.
  • Prob Required success probability.

  If a string is passed, it uses the default RANSAC parameters for the given motion model. Here are the defaults corresponding to each motion model:

  • Translation struct('Size',1, 'Thresh',0.5, 'Eps',0.5, 'Prob',0.99)
  • TranslationAndScale struct('Size',2, 'Thresh',0.5, 'Eps',0.5, 'Prob',0.99)
  • Rotation struct('Size',1, 'Thresh',0.5, 'Eps',0.5, 'Prob',0.99)
  • Rigid struct('Size',2, 'Thresh',0.5, 'Eps',0.5, 'Prob',0.99)
  • Similarity struct('Size',2, 'Thresh',0.5, 'Eps',0.5, 'Prob',0.99)
  • Affine struct('Size',3, 'Thresh',0.5, 'Eps',0.5, 'Prob',0.99)

  By default is it set to 'Affine'.