                         Basement sequence matches
                         -------------------------

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

  bt.nview-corners      Corner matches
  bt.nview-lines        Line matches

Match format: (e.g. nview-corners)
  Each row of the file corresponds to one 3d feature preimage and contains 11 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.
