Russian 

Fig.9 
To avoid superfluous losses
of time, the operation of rough choice of the contour points concerning
to the flowing contiguous segment was applied. In the beginning for an evaluation
of coincidence measure gradient of chosen contour points (the list of
references to their initial set is formed) which lay inside a wide rectangle
enclosing the contiguous segment in its flowing position (such neighbourhood
is shown by fat primes on fig.12).
Fig.12 
Operations
of deletion and preliminary choice have not only engineering sense.
A solution of basic problems depends on their organization too. In particular,
ability of the procedure to understand complicated situations depends
on their organization,  at processing of false concentrations of
contour points, in the case of capture of several segments. In similar
cases the number of steps noticeably increased (sometimes so, that it was
necessary to discontinue compulsorily process of searching). Detection
of such situations was carried out by criterion of filling ratio of resulting
segments by contour points. An example of such situation is shown on fig.11.
On this picture it is shown the initial (dotted line) and finite (solid
line) positions of the contiguous segment, corresponding to process of search
of one local maximum. Apparently, the right branch of the initial contiguous
segment has not had time to be rounded along the corresponding piece
of the contour line and intersected an adjacent contour.

Fig.11 
This example
illustrates common logic of solution of complicated situations.
To solve them it is necessary to begin from the outside  from
the "free" ends of entering lines.