Aspect ratio of an image is the image’s width to height
ratio. In order to avoid black bars in the sides of your iMovie video, you must
use the correct aspect ratio for your project. Most videos today have either 4
: 3 or the 6 : 9 (also called widscreen)
aspect ratio. It’s good if you know what
aspect ratio the video you are importing to iMovie has.
You can learn more about aspect ratios here.
How to have the right aspect ratio for your iMovie project?
The only time when you will get to determine your iMovie
video’s aspect ratio is when you first create your project.
To create a new project, go to File -> New Project.
A new window will pop up asking you to name the project. Be sure to give your project a unique, appropriate name.
Under the Aspect Ratio section, you can choose between 4 : 3
and Widescreen aspect ratios.
That's it! Now you can enjoy creating videos without any disproportionate dimensions. =)
