Now, to add animated overlays to this media file, in the right panel, click on the Graphics icon. This will show you the available animated matte overlays. Drag the animated matte overlay you wish to apply and drop it on another video track (eg. Video 2) on the Timeline just above the video clip on the Video 1 track.
Note: You can add multiple overlay clips to get different effects.
A scissor icon appears on the playhead. Click the icon to split the part of the video where overlay is not applied. This helps you retain the remaining portion of the video.
To ensure the video is revealed as the animation plays, add the Track Matte Key effect. Click on the Effects icon on the right panel and drag-and-drop the Track Matte Key effect onto the highlighted video on the Video 1 track of the Timeline.
In the Applied Effects window on the right panel, set Matte to the video track you have added it on (eg. Video 2) and Composite Using to Matte Luma.
Play the video to see the video being revealed in a dramatic way. To export the final output, select File > Export and Share. For information about various exports and share options available, see Export and share your videos.
You can use Animated Mattes as transition between two clips. Applying transition provides smooth shift from one clip to another. Transitions can also convey a tone or mood, suggest the passage of time, or separate parts of the story.
Drop Clip 2 (outgoing clip) on Track 2. From the Effects panel, select Track Matte Key effect and drag-drop it on the clip. To adjust the settings of this effect, set Matte to Video 3 (In the next step, you will add the Reveal Video Matte on track Video 3) and Composit Using to Matte Luma. Ensure the Reverse checkbox is checked.
Add the Reveal Track Matte clip on video track 3. From the Graphics panel, open the Show All drop-down and select Reveal Video Mattes. Select the matte you want to apply for the transition and drop it on the track Video 3 on the timeline such that the end of the clip aligns with the end of Clip 2. You can use Timestretch to fasten or slow down the transition effect.