If we have a bounding box (xmin, xmax, ymin, ymax)
, we can use the following algorithm to resize the bounding box by e.g. 15% on each side:
xmin -= 0.15 * (xmax - xmin) xmax += 0.15 * (xmax - xmin) ymin -= 0.15 * (ymax - ymin) ymax += 0.15 * (ymax - ymin)
Note that this will reisze the bounding box by 15% (=0.15
) on each side, i.e. the total width of the resulting bounding box will be 15% * 2 = 30% larger!
Why it works
xmin -= 0.15 * (xmax - xmin)
is the same as
xmin -= 0.15 * [width of the bounding box]