Convolution of an image.

I've done this code to convolve an image but I keep on getting this error.

Undefined function or variable 'convolve'

This is my code: (I'm using R2015a)

clc;

clear all;

close all;

RGB = imread('C:\Users\zahab\Downloads\Patrick.jpg');

subplot(1,2,1);

imshow(RGB);

I = rgb2gray(RGB);

M=[

0,0,-1,0,0;

0,-1,-2,-1,0;

-1,-2,16,-2,-1;

0,-1,-2,-1,0;

0,0,-1,0,0;

];

buffer = convolve(I,M);

subplot(1,2,2);

imshow(buffer);.

Answer 1

[Image Analyst]

I think you want

buffer = conv2(double(I),M, 'same');
imshow(buffer, []);