Resampling image :-
Resampling is used to resize an image by modifying its resolution or size in pixels.
Note that an image resolution cannot be modified without appropriately changing its size. An image file size is proportional to its squared resolution.
An image can be resampled in the three following ways:
 by changing the actual image size and size in pixels;
 by changing the actual image size without fixing size in pixels;
 by changing the image size in pixels.