What will be the solution of the following error?

%%Matlab 2014a%%

clc;
clear all;
close all;
a=imread('blood.jpg');
A=imnoise(a,'gaussian',0.01);
figure;
subplot(1,2,1);imshow(a);
subplot(1,2,2);imshow(A);
sigma=3;
cutoff=ceil(3*sigma);
h=fspecial('gaussian',2*cutoff+1,sigma);

out=conv(a,h,'same');
figure,imshow(out);
figure,imshow(out/256);
out1=conv(A,h,'same');
figure,imshow(out1/256);
w=wiener2(A,[3 3]);
figure,imshow(w);
surf(1:2*cutoff+1,1:2*cutoff+1,h)

%%%%Error%%%%
Error using conv (line 26)
A and B must be vectors.

Error in gnf (line 13)
out=conv(a,h,'same');

Answer 1

[KALYAN ACHARJYA]

a=rgb2gray(imread('blood.jpg')); 
A=imnoise(a,'gaussian',0.01); 
figure; subplot(1,2,1);imshow(a); 
subplot(1,2,2);imshow(A); 
sigma=3; 
cutoff=ceil(3*sigma); 
h=fspecial('gaussian',2*cutoff+1,sigma);
out=conv2(a,h,'same'); 
figure,imshow(out); 
figure,imshow(out/256); 
out1=conv2(A,h,'same'); 
figure,imshow(out1/256); 
w=wiener2(A,[3 3]); 
figure,imshow(w); 
surf(1:2*cutoff+1,1:2*cutoff+1,h);

[Syed Zenith Rhyhan]

Thanks a lot.It will works but give the following Warning

Warning: CONV2 on values of class UINT8 is obsolete.
         Use CONV2(DOUBLE(A),DOUBLE(B)) or CONV2(SINGLE(A),SINGLE(B)) instead. 
> In uint8.conv2 at 10
  In gnf2 at 9 
Warning: CONV2 on values of class UINT8 is obsolete.
         Use CONV2(DOUBLE(A),DOUBLE(B)) or CONV2(SINGLE(A),SINGLE(B)) instead. 
> In uint8.conv2 at 10
  In gnf2 at 12

[KALYAN ACHARJYA]

Thanks, Please read the answer comments of @walter sir.

You can convert to double and do the operation.

[Syed Zenith Rhyhan]

Thanks