Video Speed
video-speed
Adjusts the playback speed of a video by a given multiplier.
video-speed accepts a float value between 0.25 and 2.0, where 1.0 is normal playback speed. Values below 1.0 slow the video down, and values above 1.0 speed it up.
Slow Motion
When a video player slows down playback natively — by setting the playback rate to 0.25x — it simply spreads the original frames over more time. A 30fps source becomes an effective 7.5fps, producing choppy, stuttering motion.
Imgix processes the video differently. When video-speed is set below 1.0, frame interpolation is applied to synthesize new intermediate frames, so the output maintains the original frame rate at the reduced speed. The result is genuinely smooth slow motion, equivalent to footage recorded with a high-speed camera. To disable this behavior, set video-interpolation=false.
Audio pitch is also automatically corrected at all speeds, so voices and music remain natural regardless of the multiplier.
Accepted Values
| Value | Effect |
|---|---|
0.25 | Quarter speed (4× slow motion) |
0.5 | Half speed (2× slow motion) |
1.0 | Normal speed (default) |
2.0 | Double speed (2× fast motion) |