Screen Shake Effect
Screen shake effect for video and photos: the frame jolts about, from handheld jitter to an earthquake. Seeded, so it replays the same. Free, saves MP4 or GIF.
What is a screen shake effect?
Screen shake jolts the whole picture around the frame to sell an impact: an explosion, a heavy landing, a punch, a bass drop. Games made it a staple. Jan Willem Nijman of Vlambeer has described how each pistol shot in Nuclear Throne kicks the camera back six pixels and adds four to a shake value that dies away quickly.
Film uses camera shake the same way. The operator jars the camera, or the shot gets jolted in editing, to put the viewer inside a crash or an earthquake.
How to shake a video
Load a video, or a photo to record as a clip. Amount, from 0 to 50, sets how far the frame can move, in pixels of a 1080p frame scaled to yours. Speed, from 1 to 60, sets how often it jolts.
Handheld makes small 4-pixel moves at Speed 8, and Earthquake throws the frame 40 pixels at Speed 40. Mosh rolls a new random look, and Seed picks a different run of jolts.
Settings for a jittery handheld camera, a slow heavy lurch and an earthquake
Jittery handheld camera: Amount 3 and Speed 30 or higher. The frame shifts by up to 3 pixels on every frame of a 30 fps export, which feels nervous without getting violent.
Slow, heavy lurch: Amount 25 and Speed 1. The frame jumps to a new position once a second and stays there, like the deck of a ship in a swell.
Earthquake: the preset, plus the zoom from the section below so the borders stay clean. If you'd rather have smooth movement than jumps, 3D Image Spin and Card Stack Animation move a still picture in 3D loops.
How does the shake work?
On every jolt the frame jumps to a new offset, picked at random within Amount pixels across and down. There's no easing between jolts, no rotation and no blur, so it cuts straight from one position to the next.
The offsets come from the Seed and the jolt's number, so the same settings shake the same way on every export, and another Seed gives a different run. Game cameras often drive shake from smooth noise and let it fade after each hit instead, as Squirrel Eiserloh shows in his GDC talk on camera math.
How much should I zoom in to hide the shaking edges?
The frame moves without zooming in, so each jolt uncovers a strip at the border, and the picture fills that strip with a mirror image of what's just inside the edge. At Earthquake the strip can be 40 pixels deep on a 1080p frame. Editors that leave black bars there have the same problem, and the fix people give on video forums is to scale the clip up until the worst jolt stays inside the frame.
The scale follows from Amount alone, since the frame never moves more than Amount pixels of a 1080p height in either direction. Choose Open in Studio, add Zoom after Shake and set the Zoom's Amount: 0.03 covers Shake's default of 10 on a landscape or square clip, 0.04 covers 12, 0.07 covers 25, 0.12 covers Earthquake's 40 and 0.15 the maximum of 50.
A vertical 9:16 clip runs out of width first, so it needs 0.05 for Amount 10 and 0.21 for 40. The zoom costs you a little of the picture, about 7 percent of the width and height at 0.12, so keep Amount low on footage you can't crop. MP4 and WebM keep the clip's sound, and the jolts stay in place against the music.