A8 – Morphological Operations

In this activity we tried to predict the effect of dilation and erosion operations on some shapes using different structuring elements. Dilation's effect is to expand the object in the shape of the structuring element. Erosion's effect is to reduce the object by the shape of the structuring element. The shapes that were dilated and eroded were a binary image of a square (50×50) , a triangle (base = 50 , height= 30), a circle (radius 25), a hollow square (60×60, edges are 4 pixels

thick), and a plus sign (8 pixels thick and 50 pixels long for each line). The structuring elements used were 4×4 ones, 4×2 ones, 2×4 ones, cross (5 pixels long, one pixel thick). We have drawn our prediction of what would be the shape in a yellow pad. Then we verified it using the function dilate and erode in scilab.

The first image is the original image followed by the dilated and eroded images using the structuring elements (4×4 ones, 4×2 ones, 2×4 ones, cross).

Square (Dilated)

Square (Eroded)

Triangle (Dilated)

Triangle (Eroded)

Circle (Dilated)

Circle (Eroded)

Hollow Square (Dilated)

Hollow Square (Eroded)

Cross (Dilated)

Cross(Eroded)

My predicted shapes were verified using the scilab. My predictions were correct except for the cross eroded by a cross. I did not expect that square structure on the center. I expected it to be also a cross. Nevertheless, I rate myself 10 out of 10 for successfully completing the task given. It took me a lot of time to draw and predict but it was quite fun. Thank you for Ma'am Jing for personally helping me. Also thanks for Billy Narag and Jorge Michael Presto for collaborating with me.