How to Create Ken Burns Effect in FFmpeg with Zoompan

This guide demonstrates how to apply the Ken Burns effect to a static image using FFmpeg's built-in zoompan video filter. You will learn the core syntax of the filter, understand how to manipulate zoom and pan coordinates over time, and see ready-to-use command examples for zooming in, zooming out, and panning across an image without jitter.

Understanding the zoompan Filter Syntax

The zoompan filter works by cropping a moving window over an input image and scaling it to an output resolution frame-by-frame.

The most common parameters include:

  • z: The zoom factor expression for each frame. Default is 1.
  • x: The horizontal position of the crop window top-left corner.
  • y: The vertical position of the crop window top-left corner.
  • d: The duration of the effect expressed in frames.
  • s: The output video resolution (e.g., 1920x1080).
  • fps: The output frame rate (default is 25).

Useful internal variables used inside expressions:

  • in_w or iw: Input image width.
  • in_h or ih: Input image height.
  • zoom or z: Current zoom level.
  • on: Output frame number (starts at 0).

1. Zoom In to the Center

To zoom into the center of an image over 5 seconds at 25 frames per second (125 frames total):

ffmpeg -loop 1 -i input.jpg -vf "zoompan=z='min(zoom+0.0015,1.5)':x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)':d=125:s=1920x1080:fps=25" -c:v libx264 -t 5 -pix_fmt yuv420p output_zoomin.mp4
  • z='min(zoom+0.0015,1.5)': Increases zoom by 0.0015 each frame until it reaches a maximum scale of 1.5x.
  • x='iw/2-(iw/zoom/2)' and y='ih/2-(ih/zoom/2)': Centers the crop window horizontally and vertically as the zoom level changes.
  • -t 5: Limits the output duration to 5 seconds to match d=125 at fps=25.

2. Zoom Out from the Center

To start zoomed in at 1.5x and smoothly zoom out to normal scale:

ffmpeg -loop 1 -i input.jpg -vf "zoompan=z='if(lte(on,1),1.5,max(1.0,zoom-0.0015))':x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)':d=125:s=1920x1080:fps=25" -c:v libx264 -t 5 -pix_fmt yuv420p output_zoomout.mp4
  • z='if(lte(on,1),1.5,...)': Sets the initial zoom on the first frame to 1.5.
  • max(1.0,zoom-0.0015): Decreases the zoom factor per frame until it returns to 1.0.

3. Pan Across an Image (Left to Right)

To pan horizontally across an image while holding a steady zoom:

ffmpeg -loop 1 -i input.jpg -vf "zoompan=z=1.3:x='if(lte(on,1),0,x+((iw-iw/zoom)/125))':y='ih/2-(ih/zoom/2)':d=125:s=1920x1080:fps=25" -c:v libx264 -t 5 -pix_fmt yuv420p output_pan.mp4
  • z=1.3: Keeps a constant zoom of 1.3x to provide headroom for panning.
  • x='if(lte(on,1),0,x+((iw-iw/zoom)/125))': Starts at coordinate 0 and moves the crop window rightward by an equal increment across 125 frames.

Avoiding Jitter and Choppiness

The zoompan filter internally calculates crop bounds using integer pixels, which can cause micro-stuttering or jitter during slow movements. To ensure completely smooth animation:

  1. Upscale before applying zoompan: Scale the input image to a higher resolution (e.g., 4K or 8K) prior to zooming, then downscale to your target resolution.
ffmpeg -loop 1 -i input.jpg -vf "scale=8000:-1,zoompan=z='min(zoom+0.0015,1.5)':x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)':d=125:s=1920x1080:fps=25" -c:v libx264 -t 5 -pix_fmt yuv420p smooth_output.mp4
  1. Pixel Format: Always specify -pix_fmt yuv420p at the end of the command to ensure the final MP4 file is compatible with web browsers and standard media players.