                         2D geometry and matches
                         -----------------------

Files:
  ###.corners        Affine multiscale Harris corners. ASCII x y coordinates, one per line
  ###.lines          Line segments. ASCII x0 y0 x1 y1, one per line

  nview-corners      Corner matches
  nview-lines        Line matches

  The image coordinate frame (to which files ###.corners and ###.lines refer)
  is as follows: the top-left image pixel has coordinates (0,0), first axis
  aims to the right, second axis aims down.


Match format: (e.g. nview-corners)

  Each row of the file corresponds to one 3d feature (these features are in files 
  p3d and l3d) and contains #images integers (one per view) indicating
  which corner is the image of the 3D point in the associated
  view. Views in which the point does not appear are marked with an asterisk.

  For example the line
        134  *    132  131  *    *    *    *    *    *    *    *    
  indicates that this 3D point :
        corresponds to corner 134 in view 1, 
        has no match in view 2,
        corresponds to corner 132 in view 3, 
        corresponds to corner 131 in view 4,
        and has no matches through the rest of the sequence.

  Note that indices of points and lines start from zero, and are indices into
  the appropriate ".corners" or ".lines" files.