How to calculate the centroid of these bounding boxes which their 4 vertices are stored in cell array?

How to calculate the centroid of these bounding boxes which their 4 vertices are stored in cell array?

The attached file is xy coordinates of the 4 vertices of the boxes.

The coordinates are in the order:

(left-bottom), (right-bottom), (left-top), (right-top).where each coordinate is an (x, y) pair.. i.e([x1 , y1], [x2, y2], [x3 , y3 ], [x4 , y4 ])

There are 23 bounding box vertices stored in the file.

-Also, I need any angle represents the inclination of whole box with respect to the horizontal x-axis

The output should be 23 angle each represents one box

Answer 1

[Matt J]

 centroids  = cellfun(@(z) mean(cell2mat(z(:))) ,c ,'UniformOutput' ,false)

[M]

@Matt J, Thank you so much . Do you know how can I calculate the angle between each box and the horizontal x axis?

[Matt J]

You're welcome, but please Accept-click the answer if it resolves your question

Angle with x-axis: I assume that means the angle with the rays from the origin to the centroid:

rays=normalize( vertcat(centroids{:}) ,2,'n');

angles=acosd(rays(:,1))

[M]

No, I mean the angle between the top line of the box and the horizantal x-axis.

For example the angle between this line [x4, y4 ], [x3, y3 ] and x-axis .

Or the bottom line. (any angle represents the inclination of the whole box with respect to the x-axis)

Do you get me?

[Matt J]

Nope. How do you know which line is the "top"?

[M]

@Matt J, The coordinates are in the order:

(left-bottom), (right-bottom), (left-top), (right-top).where each coordinate is an (x, y) pair..

I need any angle represents the inclination of whole box with respect to the x-axis

The output should be 23 angle each represents one box

[Image Analyst]

I don't understand. Box sides are perfectly aligned and parallel with the x and y axes. So what do you mean by angle? Bounding boxes are not inclined to the axes. An angle can be defined by 3 points : the vertex point, and the 2 end points of rays. How are you defining your angle? A diagram would be helpful.