How can I rescale an image while not changing the dimension of the image? When I scale it up, it just crops the image to fit within the original size. When I scale it down, it pads the edges of the image with zeros. I want to zoom in and out about the center of the image. When using "imresize", it changes the dimensions of the image to preserve all the content. I have the image processing toolbox.
I'm not sure what you're talking about. How are you performing the scaling? Are you using the zoom() function? Are you using 'InitialMagnification' property of imshow()?
I think you want to look into imtransform, specifically the Xdata and Ydata properties. E.g. you can rotate around the center--keeping original size. Or rotate around the left corner (image moves out of view if you keep original dataspace). Etcetera for other 'focus' points and transform types.