addition of two unequal matrix

How to do a addition of a two 2dim. image i.e. (64 x 64)double and (18 x 18)double matrix,for an equation "Watermarkedimage_level1=cA2+0.01*WcA2"; this equation is for watermarking process, where both cA2 and WcA2 are the two unequal matrix which addition has to be done.

kindly provide me the Matlab code for this purpose....i'll be highly obliged

Answer 1

[Walter Roberson]

Smallerimage(64,64)=0;

Now you can add.

[Ankur Rai]

plz clear your answer, what is smallerimage(64x64), is it a matlab function..?