Bounding Box of a Mask

Problem

Find the bounding box of the non-zero pixels in a binary mask.

Return [min_row, min_col, max_row, max_col] using inclusive indices, scanned in row-major order. Return None when the mask contains no non-zero pixel.

Test cases

case 1

in: [[[0,1,0],[1,1,0],[0,0,0]]]

expected: [0,0,1,1]

case 2

in: [[[1]]]

expected: [0,0,0,0]

case 3

in: [[[0,0],[0,0]]]

expected: null

case 4

in: [[[1,0,1],[0,0,0],[1,0,1]]]

expected: [0,0,2,2]

Starter codePython

def bounding_box(mask):
    # Your code here
    pass

4 test cases · run your code against them in the editor