#661

Image Smoother

pupil · 365 · lc easy +23 · verified · 69.1% accepted · 1,237 likes · top 77%

Description

Given an m x n integer matrix img representing a grayscale image, apply a smoothing filter to every pixel: replace each cell's value with the floor of the average of all valid cells in its 3 x 3 neighborhood (including itself). Return the smoothed image.

Example 1:

Input: img = [[1,1,1],[1,0,1],[1,1,1]]

Output: [[0,0,0],[0,0,0],[0,0,0]]

Explanation:

For the points (0,0), (0,2), (2,0), (2,2): floor(3/4) = floor(0.75) = 0

For the points (0,1), (1,0), (1,2), (2,1): floor(5/6) = floor(0.83333333) = 0

For the point (1,1): floor(8/9) = floor(0.88888889) = 0

Example 2:

Input: img = [[100,200,100],[200,50,200],[100,200,100]]

Output: [[137,141,137],[141,138,141],[137,141,137]]

Explanation:

For the points (0,0), (0,2), (2,0), (2,2): floor((100+200+200+50)/4) = floor(137.5) = 137

For the points (0,1), (1,0), (1,2), (2,1): floor((200+200+50+200+100+100)/6) = floor(141.666667) = 141

For the point (1,1): floor((50+200+200+200+200+100+100+100+100)/9) = floor(138.888889) = 138

Code

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class Solution:
    def imageSmoother(self, img: List[List[int]]) -> List[List[int]]:

class Solution:
    def imageSmoother(self, img: List[List[int]]) -> List[List[int]]: