The second argument can be the scale with which you want to resize the image or the size to which you want it to be resized. Also, you can mention the interpolation method if you are scaling up the resolution
For example K = imresize(I,[100 150]) Resizes the image to 100 rows and 150 columns
Or
J = imresize(I,1.25); Scales up you present image to 1.25 times
L = imresize(I,1.5,'bilinear'); Scales the image by 1.5 times by using bilinear interpolation method
