ResizeImage is designed to change the size of images. It
can enlarge or shrink images using its weighted-pixel
averaging technique and associated filters.
What is weighted-pixel averaging?
Most programs enlarge images by duplicating existing pixels.
This results in a coarse blocky image. When shrinking images,
they remove pixels. This results in an image that isn't very clear.
ResizeImage uses a different technique. Rather than duplicating
pixels, it calculates the average value of the missing pixel based
upon the surrounding pixels, weighing each adjacent pixel
according to how much of it would have contributed to the new
pixel. When shrinking an image it combines the adjacent pixels,
again weighted according to their contribution to the new pixel,
and determines the average value of the new pixel.
The results from ResizeImage are truer to the original, allowing for
a smooth flow from pixel to pixel.