Zig-Zag Based Single-Pass Connected Components Analysis

. 2019 Apr 6;5(4):45. doi: 10.3390/jimaging5040045

Algorithm 1 Zig-zag CCA algorithm

Input: Binary image I of width W and height H
Output: A feature vector for each connected component in I

1:
$S t a r t O f L i n e : = False$
2:
for $y : = 0$ to $H - 1$ do
3:
for $x : = 0$ to $W - 1$ when y is even else $x : = W - 1$ downto 0 do ▹ Zig-zag scan
4:
if $S t a r t O f L i n e$ then
5:
ReverseNeighbourhood ▹ Algorithm 3
6:
$S t a r t O f L i n e : = False$
7:
else
8:
UpdateNeighbourhood ▹ Algorithm 2
9:
end if
10:
UpdateDataStructures ▹ Algorithm 4
11:
end for
12:
$S t a r t O f L i n e : = True$
13:
end for