iMovie
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Add video effects in iMovie on Mac
iMovie includes an array of filters you can use to modify the appearance of clips and photos. For example, you can apply a sepia filter to a clip to make it look like old film footage.
In addition, iMovie includes the following preset effect combinations that make it easy to add complex transitions to your movie:
Fade to: The “Fade to” effects create a transition from a normal clip appearance to a black-and-white, sepia, or dreamlike appearance.
Flash and Freeze Frame: Flash and Freeze Frame inserts a transition to white, and then fades in a freeze frame while simultaneously applying the Ken Burns effect.