plz help me out with this error..matrix dimension mismatch

part of my code is

img1=imread('img.jpg'); [m n]=size(img1); imnoise=img1+64*randn(m,n);

its giving an error like this

??? Error using ==> plus Matrix dimensions must agree.

Error in ==> prog4c at 6 imnoise = img1 + 64*randn([m,n]);

thanqq

Answer 1

[Kaustubha Govind]

IMREAD usually returns a 3-D matrix, but you are collapsing the size to a 2-D by using:

[m n]=size(img1);

Try:

 [m n q]=size(img1);
 imnoise=img1+64*randn(m,n,q);

[Rajesh Kumar]

my input is color img..so its in 3D..i converted to gray and got the output...thanq