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Watch the tutorial
Step 1: Add the Transform effect
Select your clip on the timeline. In the video, the clip is a nested sequence, which is a handy way to keep the effect on one layer, but a normal clip works too. Open the Effects panel (Window > Effects) and search for transform. Pick the Transform effect in Video Effects > Distort, not the folder with the same name, and apply it to your clip.
Faster with BetterFX: skip the Effects panel. Press your BetterFX shortcut, type the first letters of Transform and press Enter to apply it to the selected clip. Get BetterFX
Step 2: Draw a mask around the subject
Open the Effect Controls panel and find Transform. Under the effect name there are mask tools: an ellipse, a rectangle and a Pen tool. Click the Rectangle tool, then draw a box in the Program Monitor around the part of the picture you want to stretch, such as a character's body. Only the area inside the mask will be stretched, so the rest of the frame stays untouched.
Step 3: Turn off Uniform Scale
Scroll down in the Transform settings and find the Uniform Scale checkbox. Untick it. This unlocks Scale Height and Scale Width so you can change them separately. If you leave it ticked, the picture grows in both directions and you will not get a stretch. The mask settings above it include Mask Feather, which softens the mask edge, so raise it a little if the edge of the stretched area looks too sharp.
Step 4: Keyframe Scale Width
Move the playhead to the point where the stretch should begin, and click the stopwatch next to Scale Width to set a keyframe at its normal value. Then move forward to where the stretch should peak and increase Scale Width. In the video the width goes up to a little under double its normal size, but you can go higher for a more extreme stretch.
Step 5: Play it back and fine tune
Press the spacebar to watch the stretch. The masked area now grows wider over time, while the rest of the scene stays still. Adjust the second keyframe if the stretch is too weak or too strong, and move the mask if the edge of the subject pokes outside it.
Tips
- Make it bounce. Add keyframes that stretch the subject out and back to normal for a cartoon-style wobble. Our easing guide shows how to smooth them.
- Try Scale Height too. Stretching the height instead gives a tall, skinny look, and you can animate both for a squash-and-stretch effect.
- Match the mask to the motion. If the subject moves, keyframe the mask so it keeps following it.
FAQ
How do I stretch part of a video in Premiere Pro?
Add the Transform effect, draw a mask around the area, untick Uniform Scale and animate Scale Width or Scale Height.
Why is my whole video stretching instead of just the subject?
The mask is missing or too big. Draw a mask with the Transform effect's own mask tool, and make sure it covers only the part you want to stretch.
Can I stretch a clip without a mask?
Yes. Without a mask the whole clip stretches. That works when you want to stretch the entire frame, such as for a punchy zoom effect.
Effects like this are quick to apply when you can reach them in a keystroke. Try BetterFX for Premiere Pro
