How to crop a video?

After you added a video to the program, mouse over it and you will see the Edit Options button (Gear icon with a down arrow). Click it to show all tools and select Cropping from the list. Alternatively, simply click the Cropping button below the Preview Window after highlight a video. 

There are 3 aspect ratio options: 16:9, 4:3 and Manually in the Preview window.

The 16:9/4:3 options will restrict your video the standard aspect ratio. You can drag the rectangle to adjust it size but without changing the aspect radio.

The Manually option lets you crop a video without any limit. Just drag the four corners to adjust the rectangle. Any region out of the rectangle will be cut off.

Click the Done button to save the changes. Click the Reset button to cancel all changes without saving.