Change duration and speed of clips
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.
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.
Use one of the following options to change the speed or duration of a clip:
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.
Use the Speed/Duration command
In the Timeline panel or Project panel, select one or more clips. Ctrl-click (Windows) or Command-click (Mac OS) clips to select a non-contiguous group of clips in the Project panel.
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:
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.
Clips with speed changes are indicated with a percentage of the original speed.
Use the Rate Stretch tool
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.
Use Time Remapping
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 clip is shaded blue. A horizontal rubber band that controls the speed of the clip appears across the center of the clip. A white speed-control track appears in the upper portion of the clip, just below the clip title bar. If it is hard to see the clip, zoom in to make enough room.
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.
Vary changes to speed or direction with Time Remapping
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.
Using Time Remapping, you can perform the following:
Vary change to clip speed
The clip is shaded blue. A horizontal rubber band that controls the speed of the clip appears across the center of the clip. A white speed-control track appears in the upper portion of the clip, below the clip title bar.
A. Speed keyframe B. White speed-control track C. Rubber band
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.
Both the speed and duration of the segment change. Speeding up a segment of a clip makes the segment shorter, and slowing down a segment makes it longer.
The change of speed eases in or eases out according to the curvature of the speed ramp.
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.
Move an unsplit speed keyframe
Move a split speed keyframe
In the white control track area of the clip, drag the gray-shaded area of the speed transition into its new position.
Play a clip backward, then forward
The clip is shaded blue. A horizontal rubber band that controls the speed of the clip appears across the center of the clip. A white speed-control track appears in the upper portion of the clip, just below the clip title bar. If it is hard to see the clip, zoom in to make enough room.
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.
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.
The change of speed eases in or eases out according to the curvature of the speed ramp.
Remove the Time Remapping effect
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 make this panel active, click the Effect Controls tab.
To open Time Remapping, click the triangle next to it.
To set it to the off position, click the Toggle Animation button next to the word Speed.
This action deletes any existing speed keyframes, and disables Time Remapping for the selected clip.
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.
Change the default duration for still images
Choose Edit > Preferences > Timeline (Windows) or Premiere Pro > Preferences > Timeline (Mac OS).
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.
Optical flow option for time remapping and speed/duration
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.
Change duration and speed of clips
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.
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.
Use one of the following options to change the speed or duration of a clip:
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.
Use the Speed/Duration command
In the Timeline panel or Project panel, select one or more clips. Ctrl-click (Windows) or Command-click (Mac OS) clips to select a non-contiguous group of clips in the Project panel.
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:
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.
Clips with speed changes are indicated with a percentage of the original speed.
Use the Rate Stretch tool
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.
Use Time Remapping
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 clip is shaded blue. A horizontal rubber band that controls the speed of the clip appears across the center of the clip. A white speed-control track appears in the upper portion of the clip, just below the clip title bar. If it is hard to see the clip, zoom in to make enough room.
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.
Vary changes to speed or direction with Time Remapping
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.
Using Time Remapping, you can perform the following:
Vary change to clip speed
The clip is shaded blue. A horizontal rubber band that controls the speed of the clip appears across the center of the clip. A white speed-control track appears in the upper portion of the clip, below the clip title bar.
A. Speed keyframe B. White speed-control track C. Rubber band
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.
Both the speed and duration of the segment change. Speeding up a segment of a clip makes the segment shorter, and slowing down a segment makes it longer.
The change of speed eases in or eases out according to the curvature of the speed ramp.
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.
Move an unsplit speed keyframe
Move a split speed keyframe
In the white control track area of the clip, drag the gray-shaded area of the speed transition into its new position.
Play a clip backward, then forward
The clip is shaded blue. A horizontal rubber band that controls the speed of the clip appears across the center of the clip. A white speed-control track appears in the upper portion of the clip, just below the clip title bar. If it is hard to see the clip, zoom in to make enough room.
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.
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.
The change of speed eases in or eases out according to the curvature of the speed ramp.
Remove the Time Remapping effect
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 make this panel active, click the Effect Controls tab.
To open Time Remapping, click the triangle next to it.
To set it to the off position, click the Toggle Animation button next to the word Speed.
This action deletes any existing speed keyframes, and disables Time Remapping for the selected clip.
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.
Change the default duration for still images
Choose Edit > Preferences > Timeline (Windows) or Premiere Pro > Preferences > Timeline (Mac OS).
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.
Optical flow option for time remapping and speed/duration
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.
Оптический поток
Рассмотрим новый параметр «Оптический поток» для перераспределения времени и настройки скорости/продолжительности, появившейся в обновлении Adobe Premiere Pro CC 2015.1 (9.1.0).
Технология «Оптический поток» выполняет интерполяцию новых промежуточных кадров, изменяя время для преобразования обычного видеоряда в качественный и плавный видеоряд в режиме замедленной съемки. Теперь, помимо параметров Выборка кадров / Frame Sampling (3:2 pulldown) и Наложение кадров / Frame Blending (смешивание соседних кадров) пользователям доступна функция Оптический поток / Optical Flow.
Все три функции доступны в следующем меню: в меню Клип > Параметры видео > Интерполяция времени (Clip > Video Options > Time Interpolation), в диалоговом окне Скорость/продолжительность клипа (Ctrl+R) и в контекстном меню Клип / Clip.
Помимо этого, чтобы выполнить интерполяцию кадров для экспорта с другой частотой кадров, можно выбрать функцию Оптический поток в диалоговом окне Настройки экспорта / Export Settings.
Итак в окне Скорость/продолжительность отсечения (Clip Speed / Duration) изменяем параметр Скорость / Speed выставив значение 24%.
После выбора Интерполяция времени: Оптический поток, получаем красную линию над клипом.
При воспроизведении видео с измененной скоростью, загрузка центрального процессора: 71% и оперативной памяти: 3.28Гбайт.
Загрузка GPU видеокарты GeForce GTX 960: 8%.
Отображение различных параметров при предварительном просмотре линейки времени:
Теперь выбираем: Выборка кадров. Нажимаем на кнопку: ОК.
Желтая полоса над клипом на таймлайне:
Получаем также загрузку GPU равную 8%.
Теперь отключаем GPU движок Файл > Настройки проекта > Общие, выбрав: Только программное ускорение ядра Mercury Playback.
В обоих режимах (Оптический поток и Выборка кадров) получаем красную полосу над клипом в котором изменяем скорость воспроизведения. А также загрузка GPU снизилась с 8% до 5%.
Загрузка центрального процессора осталась та же:
Отображение различных параметров при предварительном просмотре таймлайна в режиме: Software Render System.
Теперь рассмотрим загрузку CPU/GPU с включенным/отключенным режимом: Аппаратное GPU-ускорение ядра Mercury Playback (CUDA). Настройки экспорта:
Включен Аппаратное GPU-ускорение ядра Mercury Playback (CUDA), выбираем, Интерполяция времени: Оптический поток. И нажимаем на кнопку:
После 11% просчитанного, отображается оставшееся время: 1 час и 5 минут.
Загрузка GPU (GeForce GTX 960) – 99%.
Загрузка центрального процессора: 32%, и видим несимметричную загрузку потоков.
Выбираем движок: Только программное ускорение ядра Mercury Playback.
После 12% просчитанного материала, итоговое время просчета: 1 час и 29 минут.
GPU в финальном рендеринге не участвует.
Загрузка центрального процессора: 100%.
Процессор Intel Core i5-5675C работал на тактовой частоте 3.6ГГц.
*В обновлении Premiere Pro CC 2015.2 исправлено: финальный кадр из вложенной последовательности отображаются неправильно при использовании оптического потока с поддержкой GPU ускорения.
*Сравниваем различные виды замедления с Оптический потоком.
*Проверим скорость работы GPU с функцией Оптический поток / Optical Flow в новой версии программы с установленным обновлением Adobe Premiere Pro CC 2015.4.
Исходник: AVCHD 2.0 (1080р60).
Настройки экспорта, переводим 60fps в 24fps.
Загрузка центрального процессора Intel Core i7-3770: 45% и оперативной памяти при рендеринге: 2.9 Гбайта.
GPU видеокарты построенной на чипсете AMD Radeon RX 460 было загружено на 100% и в пике потребляло (питание только от шины PCIe 3.0): 55.4Вт.
Итоговое время рендеринга: 2 минуты и 37 секунд.
Отключаем GPU ускорение: Только программное обеспечение Mercury Playback Engine.
Загрузка центрального процессора: 99%.
Процесс Adobe Media Encoder.exe грузит CPU на 99%, и оперативную память на 2.2Гбайта.
Выполняем команду: Файл > Показать журнал (Ctrl+L) и в AMEEncodingLog смотрим время рендеринга: 7 минут и 42 секунды.
*Тестирование эффективности использования интегрированной графики в процессорах для просчета ретайминга с помощью Оптического потока.
Тестируем производительность работы Optical Flow с помощью дискретных видеокарт.
