Digital Geometry in Image Processing

Digital Straight Lines and Planes 109

3.2.5.1 (n)-characterization [76, 79]

This is the simplest characterization of a chain code and is g iven by the

number of elements in it.

g

MP O

(n) = n

g

BLUE

(n) = (π/4)

√

2n = 1.111n

For both estimators, RDEV tends to be a constant as n → ∞. This means

that the accuracy of these estimators cannot be increased beyond a certain

point, even by increasing the sampling density. RDEV (g

MP O

(n)) = 16% a nd

RDEV (g

BLUE

(n)) = 11%.

3.2.5.2 (n

e

, n

o

)-characterization [76, 7 9]

In (n

e

, n

o

)-characterization, the number of 0s in a chain code is computed

as n

e

and the number of 1s in a chain code is computed as n

o

. This is also

known