Digital Geometry in Image Processing

132 Digital Geometry in Image Processing

Note that, in continued fraction, [q

1

, q

2

, . . . , q

n

] implies

1

q

1

+

1

q

2

+

1

.

.

.

1

q

n−1

+

1

q

n

.

As explained in the coming section, we g et the corresponding chain-code

(Fig. 4.2; see also Chapter 1) representation from this as 0

8

(0

7

1)

4

(here, k

consecutive 0s are written as 0

k

for brevity), which defines the period of the

DSL. It indicates that there are four consecutive runs of identical composition,

i.e., 0

7

1, following (and preceding) a single run of 0

8

. A run is given by the

maximum sequence of contiguous digital po ints lying on the same horizontal

or vertical line. The first and the last runs of the DSS should be ig ...