Get coordinates of edges - Image Processing

I am performing Roberts method for edge detection. But my aim is to get the coordinates of the edges after applying Roberts method or any other method.

Before Roberts method:

After Roberts Method:

Further more i want to calculate the coordinate of these 4 vertices.

Is there is any solution for this problem ?

Answer 1

[KALYAN ACHARJYA]

Lets say image_test is the output binary image (After Roberts Method)

data=corner(image_test);
r_data=data(:,1);
c_data=data(:,2);

min_colm=min(c_data);
idx1=find(c_data==min_colm);
ver1=[r_data(idx1(1)),min_colm]

max_colm=max(c_data);
idx2=find(c_data==max_colm);
ver2=[r_data(idx2(1)),max_colm]

min_row=min(r_data);
idx3=find(r_data==min_row);
ver3=[min_row,c_data(idx3(1))]

max_row=max(r_data);
idx4=find(r_data==max_row);
ver4=[max_row,c_data(idx4(1))]

Please verify?

[Rajbir Singh]

Thank you Sir, it works for me.

[KALYAN ACHARJYA]

It's my pleasure @Rajbir