Algorithm 2 Morphological opening

1. BEGIN

2.  VOID open1d(image,u) {

3.   FOR i in 1,length(image.lines) do

4.    line = image.lines[i]

5.    filtered = []

6.    FOR j in 1,length(line.runs) do

7.      if runs[j].width() >= u then

8.      filtered.append(line.runs[j])

9.    ENDFOR

10.    image.lines[i] = filtered

11.   ENDFOR

12. END