Add video filters in iMovie on iPhone
iMovie includes a number of video filters you can use to enhance or change the look of your clips, such as converting a colour clip to black and white. You can add video filters to clips in your project or to the entire project.
Add a filter to a single clip
With your project open, tap a video clip in the timeline to reveal the inspector at the bottom of the screen.
Tap the Filter button
.Tap a filter to preview it in the viewer.
To turn off filters, tap None.
To adjust the strength of the filter, drag the slider below the timeline left or right.
When you’ve finished, tap outside the filters to dismiss them.
Add a filter to a project
When you add a filter to a project, it’s applied to all clips in the project by default. You can still add or remove filters for individual clips in the timeline.
With the project open, tap the Project Settings button
.Tap a filter to select it.
Tap Done.