With this tool you can quickly higlight specific area on an image based on the coordinates x, y, width, height
You have an image of a cat
You know the program cuts somthing at these coords: 100 0 250 150 but you don't know what exactly it is. You cannot easily imagine what the field defined by the coordinates looks like.
All you need to do is paste url image to the URL input field and coordinates separated by spaces

