`smoothdata2`

Smooths a matrix in two dimensions.

Category: Data Import and Analysis > Preprocessing Data

Syntax

B = smoothdata2(A)

Smooths with a default method and window.

B = smoothdata2(A, method, wlen)

Uses method with a window of wlen, a scalar for a square window.

Description

This is the two-dimensional counterpart of smoothdata: each element is replaced by a statistic of its neighborhood in both directions, so rows and columns are smoothed together. With 'movmean' and a 3 by 3 window each interior point becomes the mean of its eight neighbors and itself; windows are truncated at the edges.

A median window removes salt-and-pepper type noise, while a mean window gives a blur.

Input arguments

A: Numeric matrix, such as an image or gridded measurements.
method: 'movmean', 'movmedian' or 'gaussian'.
wlen: Window size, scalar or [rows cols].

Output arguments

B: Smoothed matrix of the same size as A.

Example

Neighborhood mean

A = [1 2 3; 4 5 6; 7 8 9];
smoothdata2(A, 'movmean', 3)

Output

ans = 3×3

    3.0000    3.5000    4.0000
    4.5000    5.0000    5.5000
    6.0000    6.5000    7.0000

smoothdata2