The speed of a clip is the rate at which it plays back compared to the rate at which it was recorded. The duration of a clip is the length of time it takes to play from the In point to the Out point. You can set a duration for video or audio clips, letting them speed up or slow down to fill the duration.
You can change the speed and duration for one or more clips at a time. Premiere Pro offers several ways to modify the speed and duration of clips. You can use the following options:
You can apply Optical Flow only from the timeline or Export Settings dialog box, and not from the Project panel. Timeline Search provides you with advanced search options that let you find and manage clips in complex timelines. For more information, see Find assets.
You can apply Speed/Duration changes at the Project clip level or at the Sequence clip level. Changes made at the project level are respected when adding new instances into a sequence. It is different from master clip effects though, because Speed/Duration changes are not ripped into existing instances of that clip in your sequence.
Do any of the following:
- To change the duration without changing the speed of the selected clips, click the gang button so that it shows a broken link. Unganging also allows you to change the speed without changing the duration.
- To play the clips backward, check Reverse Speed.
- To keep the audio at its current pitch while the speed or duration changes, check Maintain Audio Pitch.
- To keep the clips following the changing clips next to them, click Ripple Edit, Shifting Trailing Clips.
If the Ripple Edit Tool stops working, make sure that the Composite Preview During Trim option is deselected from the wrench tool in the timeline.
The Rate Stretch tool provides a quick method to change the duration of a clip in the Timeline while simultaneously change the clip's speed to fit the duration.
For example, you have a gap in your sequence of a specific length and you want to fill that gap with some speed-altered media. You do not care so much about the speed of the video, make sure it fills that gap at whatever speed it has to be. Rate stretch allows you to stretch or compress the speed to the percentage needed.
You can change a clip’s speed to fit a duration using the Rate Stretch tool in Premiere Pro. Select the Rate Stretch tool and drag either edge of a clip in a Timeline panel.
You can vary the speed of the video portion of a clip. Use Time Remapping to create slow motion and fast motion effects within a single clip.
The playback speed of the video portion of the clip changes and its duration expands or contracts depending on whether its speed is increased or decreased. The audio portion of the clip remains unchanged by Time Remapping, although it remains linked to the video portion.
When you lengthen a clip in a sequence by slowing its speed, it does not overwrite an adjacent clip. Instead, the clip expands until it touches the edge of the adjacent clip. Adobe Premiere Pro then pushes remaining frames into the tail of the lengthened clip. To recover these frames, create a gap after the clip and trim its right edge to reveal them.
You can speed up, slow down, play backward, or freeze video portions of a clip using the Time Remapping effect. For example, take a clip of someone walking. You can show the person moving forward quickly, slowing suddenly, stopping mid-step, and even walking backward, before resuming the forward motion.
You can apply time remapping only to instances of clips in a Timeline panel, not to master clips. When you vary the speed of a clip with linked audio and video, the audio remains linked to the video, but remains at 100% speed. The audio does not remain synchronized with the video.
Speed keyframes can be applied in the Effect Controls panel, or on a clip in the Timeline panel. A speed keyframe can be split to create a transition between two different playback speeds.
When first applied to a track item, any change in playback speed on either side of a speed keyframe is instantaneous at that frame. When the speed keyframe is dragged apart and spread out beyond one frame, the halves form a speed change transition. Here, you can apply linear or smooth curves to ease in or ease out the change between playback speeds.
It is best to apply time remapping controls to a clip in its own video track. Slowing a portion of the clip makes it longer. If a second clip follows the lengthened clip in the video track, the lengthened clip is automatically trimmed where the second clip begins. To recover trimmed frames, click the Track Select Tool. Shift-drag the second clip toward the right. All clips lying to the right move to the right. Click the Selection tool, and drag the right edge of the lengthened clip to the right, exposing its trimmed frames.
Ctrl-click (Windows) or Command-click (Mac OS) at least one point on the rubber band to set a keyframe. Speed keyframes appear near the top of the clip, above the rubber band in the white speed-control track. Speed keyframes can be split in half, acting as two keyframes for marking the beginning and end of a speed-change transition. Adjustment handles also appear on the rubber band, in the middle of the speed-change transition.
Drag the rubber band on either side of the speed keyframe up or down to increase or decrease the playback speed of that portion. (Optional) Press Shift while dragging to limit the speed change values to 5% increments.
Shift-drag the speed keyframe to the left or right to change the speed of the portion to the left of the speed keyframe.
Speed and Velocity values for the Time Remapping effect are shown in the Effect Controls panel for reference only. You cannot edit these values directly there.
In the white control track area of the clip, drag the gray-shaded area of the speed transition into its new position.
Ctrl-drag (Windows) or Command-drag (Mac OS) a speed keyframe (both halves) to the place where you want the backward motion to end. A tool tip shows the speed as a negative percentage of the original speed. The Program monitor displays two panes: the static frame where you initiated the drag, and a dynamically updating frame that reverses playback returns to before switching to forward speed. When you release the mouse button to end the drag, an extra segment is added for the forward playback portion. The new segment has the same duration as the segment you created. An extra speed keyframe is placed at the end of this second segment. Left-pointing angle brackets appear in the speed-control track, indicating the section of the clip playing in reverse.
The segment plays backward at full speed from the first keyframe to the second. Then, it plays forward at full speed from the second to the third keyframe. Finally, it returns to the frame at which the backward motion began. This effect is called a palindrome reverse.
You can create a segment that plays in reverse and doesn't return to forward playback. Use the Razor tool or the Trim tool to remove the segment of the clip with the forward playback section. For more information, see Trimming clips.
(Optional) You can create a speed transition for any part of the change in direction. Drag the right half of a speed keyframe to the right, or the left half to the left.
A gray area appears between the halves of the speed keyframe, indicating the length of the speed transition. A blue curve control appears in the gray area.
If the blue curve control does not appear, click in the gray area.
You cannot toggle the Time Remapping effect on and off like other effects. Enabling and disabling Time Remapping affects the duration of the clip instance in a Timeline. Once the Time Remapping effect has been disabled, all the keyframes are deleted.
To re-enable Time Remapping, click the Toggle Animation button back to the 'on' position. You cannot use Time Remapping with this button in the 'off' position.
Changing the default duration of still images does not affect the duration of still images that are already part of a sequence or that have already been imported. Reimport the images after you change the default duration to get a different duration for the images.
You can also create a time lapse from still images. For more information, see Create time lapse video from still images.
The Optical Flow feature in Premiere Pro uses frame analyses and pixel motion estimation to create brand new video frames, resulting in smoother speed changes, time-remapping, and frame-rate conversion.
The Optical Flow option in the Time Interpolation menu (Clip > Video Options > Time Interpolation > Optical Flow) allows you to interpolate missing frames for time remapping and produce better looking and smoother slow motion from conventionally shot footage.
Since the optical flow library cannot sustain real-time playback, as it happens with the existing Frame Blend function, Premiere Pro uses the time-consuming Optical Flow only for Time Remapping for high quality renders. For low quality or draft rendering, the faster Frame Sample interpolation is used even while the Optical Flow is enabled. To see the optical flow effect, render your sequence. Choose Render In to Out or hit Enter to do that
Optical Flow interpolation is ideal for modifying the speed of clips that contain objects with no motion blur, which are moving in front of a mostly static background that highly contrasts with the object in motion.
If video plays in fast forward, go to, Edit > Preferences > Audio Hardware and change the default input of to none.
The Time Interpolation setting in the Export Settings dialog box (File > Export > Media) allows you to change the frame rate of the exported file by using Optical Flow to interpolate the missing frames. For example, if you have a 30-fps footage that you want to export at 60 fps without repeating every frame, you can export the media with the Optical Flow option in the Time Interpolation drop-down box selected.
In some footage, using Optical Flow for creating smoother motion does not produce the desired results. In such scenarios, you can use one of the other time interpolation options--Frame Sampling or Frame Blending. Frame Sampling repeats or removes frames as required, to reach the desired speed. Frame Blending repeats frames, and it also blends between them as required, to help smooth out the motion.
You can access all the time interpolation methods from within Premiere Pro using one of the following options:
- Choose Clip > Video Options > Time Interpolation > Frame Blending | Frame Sampling.
- Right-click on the clip in a sequence and choose Time Interpolation > Frame Blending | Frame Sampling.
- Open the Speed/Duration dialog box and use the Time Interpolation drop-down.
- Open the Export Settings dialog and use the Time Interpolation drop-down (this method only applies to exported media).