It will also reset the internally stored original width and height, as if the image was just loaded in the LqrCarver object.

This function must only be invoked over initialised LqrCarver objects.

This function is called internally each time the rescaling direction changes, or at each new step in a multiple-step enlargement, but, when calling it manually, the discarded visibility map will not be dumped automatically by it; use the functions lqr_vmap_dump(3) or lqr_vmap_internal_dump(3) in order to save it before invoking this function.