Recent iPhone models and iOS versions have a new feature called SLO-MO which allows user to record slow motion videos using iPhone. But it lacks the flexibility to slow down video, speed up video, edit iPhone video speed like 1/4X, 1/2X, 3/4X, 2X, 3X, etc. And if you use an earlier iPhone model or iOS version, the stock Camera app does not support slow-motion or time-lapse video at all.
Sometimes, we may like to edit the playback speed of our videos. When you want to watch long videos in a short time, you can increase the playback speed; when you need your audiences to focus on certain parts of the video, you can slow it down.
Today, we will show you how to edit video playback speed on iPhone, not only those slow-mo videos but also videos at regular speed. You will learn how to convert or change slow-mo video to normal speed, and turn normal videos to slow-motion videos or speed up videos on iPhone.
Duplicate video before editing
It is strongly recommended that you backup a file before editing. That way if you directly modified the original video file in the photo library and made a mistake, you can revert to your saved copy.
Open the Photos app on your iPhone and find the video that you want to adjust the speed for. Tap on the video to open it, then tap on the More menu button, which looks like an ellipsis in a circle, in the top-right corner of the screen. Then choose Duplicate from the drop-down menu to create a copy of the original video in your photo library.
Change slow motion video to normal speed
Open the Photos app on your iPhone. Switch to the Albums tab from the screen bottom. Scroll down to the Media Types section, tap on Slo-mo to find all videos recorded in slo-mo mode. Open a video shot in Slo-mo mode to open it in full screen, then tap Edit in the top-right corner of the screen.
You will see the white vertical bars beneath the frame viewer. The lines closer to each other reflect the video’s regular speed. The lines that are far apart from each other indicate the video’s slow speed. Two longer bars separate the slow motion from the video at normal speed. You can drag them to set where the video is played in slow motion. To increase the speed of a slo-mo video or change the whole slow motion video to normal speed, drag the left long bar to the right one or drag the right long bar to the left one. Tap on Done to save the change.
Edit playback speed of regular videos in iMovie
As to those regular videos or videos at regular speed, you can make use of iMovie, the built-in video editor, to speed them up or reduce them down.
Open the iMovie app on your iPhone. On the app’s Projects viewer, tap Start New Project > Movie to create a new project or select an existing project you want to edit.
Select the video clip that you want to adjust the speed for and add it to the Timeline in iMovie.
Tap on the video clip in the Timeline to reveal more tools at the bottom. Tap the Speed icon in the bottom left corner of the screen. It looks like a speedometer.
You will see a slider that helps reduce or increase your video’s speed. To speed up your video, then drag this slider to the right (towards the rabbit); to slow down your video, drag this slider to the left (towards the turtle). We know that turtles creep along at very slow speed and there is a common saying in English that goes “quick as a bunny.” Adjust the speed by moving the slider left or right, play the video to see the change and tap Done in the top left corner of the screen once you have chosen the speed you want. You will be taken back to the Projects viewer where you can save, export and share the video.
That’s it! You have now successfully adjusted the speed of a video clip in iMovie on your iPhone.