How are bounding boxes defined in MATLAB?

I extracted bounding box positions from MATLAB's video labeller app. However, I can't seem to understand how the position is formatted. The initial bounding box position shows four numbers, while the rest show 8 numbers.
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In each case, the second row looks to be the same as the first row of the group and so can be removed / ignored.
Thanks. I also wanted to know the format of the bounding box numbers. As per the documentation, the numbers are [x y width height] in pixels, what is x and y?
x and y are used in Cartesian coordinate sense. x is distance along the horizontal axes (left/right) starting from the lower left corner, and y is distance along the vertical (up/down) axes starting from the lower left corner. x corresponds to columns (not rows) and y corresponds to rows (not columns) so you need to reverse x and y if you want to index into an array.
Side note: imcrop has an off-by-one in what it crops. If for example you give it the bounding box 1 1 5 5 then instead including only YourMatrix(1:5,1:5,:) it extracts YourMatrix(1:6,1:6,:)

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R2019b

Asked:

on 15 Dec 2019

Commented:

on 31 Dec 2019

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