Rate stretch
A rate stretch changes a clip’s length by changing its speed, not by trimming it. The clip still plays all of the source it showed, faster or slower, so it’s the quick way to make a shot fit by eye.
- Keys
- ⌥-drag
- Where
- Timeline: a media clip's end edge
- Agent tools
rate_stretch
Stretch a clip
Section titled “Stretch a clip”-
Hold ⌥.
-
Press on the end edge of a clip of a video or audio file, and drag. The timeline shows the result as you drag.
-
Let go.
The stretch lands as one undo step, Rate Stretch. The new rate is the length of source the clip shows divided by its new length, so a 10 s clip at ×1 dragged to 5 s plays at ×2.
Frame Job reads ⌥ when you press, so hold it before the drag starts. ⌥⇧ on an edge is a roll, not a stretch.
Actions keep their fraction of the clip. Captions over the clip are re-timed in the same step, which is then named Rate Stretch and Re-time Captions, and they jump when you let go. See Captions follow a speed change.
Snapping
Section titled “Snapping”A rate stretch snaps like any other edge drag. Hold ⌘ during the drag to turn snapping off for it. See Snapping.
Which edges and clips stretch
Section titled “Which edges and clips stretch”| You drag with ⌥ | What happens |
|---|---|
| A media clip’s end edge | A rate stretch |
| A clip’s start edge | An ordinary trim |
| The end edge of a still, text, shape, graphic or any other clip | An ordinary trim, with the undo step Trim Clip |
| An edge on a locked track | Nothing. The edge doesn’t move. |
| The end edge of a clip linked to its detached sound | Nothing, with no beep and no reason, until you attach it |
Where a stretch stops
Section titled “Where a stretch stops”The clip stops following the drag when the next step would break a limit, and it lands at the last length that worked:
- Rate limits. The stretch can’t need a rate outside ×0.1 – ×1000.
- One frame. The clip can’t get shorter than one frame.
- The next clip. A stretch into the next clip follows the same overlap rule as any slowed clip, so the later clip gains a transition across an allowed overlap.
Drag back inside the limit and the clip follows you again.
A ramped clip
Section titled “A ramped clip”On a clip with a speed ramp, the whole ramp stretches with the clip and keeps its shape. The stretch stops where any of its rates would pass the limits. See Edit a ramped clip.
Stretching past ×12
Section titled “Stretching past ×12”If a stretch takes a clip with sound past ×12, Frame Job puts the stretch back and asks first.
- Set Speed applies the stretch you made.
- Cancel leaves the clip as it was.
See Sound at high speed.
With an agent
Section titled “With an agent”rate_stretch takes clip and to_end, the clip’s new end on the timeline, and both are required. A text, shape, image or freeze clip is an error. The reply’s captions_retimed lists the captions that moved, and captions_removed those whose speech the clip no longer plays. See rate_stretch.