The main window allows you to select the image you want to resize or modify. You can manually configure the width and the height. 

This program enables you to apply various effects to your images, and you can also choose the degree of these changes. 

The Resize window shows you the current dimensions of your picture and you get to change them as much as you want. 

The Effect menu displays all the effcts that you can apply to your images, also showing the keyboard shortcuts for them.