Frame blending что это
Как добавить эффект ускорения в Adobe After Effects для видео с дрона
Russian (Pусский) translation by Yuri Yuriev (you can also view the original English article)
На съёмках с дрона часто встречается стильный эффект ускорения. Им пользуются многие популярные блоггеры Youtube, вроде Casey Neistat.
Сначала съёмка полёта идёт с нормальной скоростью. Затем, для оживления, кадры начинают ускоряться и замедляются снова. Это сокращает время просмотра без потерь вида окружающего пространства.
1. Заходим в Time Remapping
Сначала включите Time Remapping кадров. (Не забудьте загрузить пример клипа для этого урока!) Щёлкните правой кнопкой мыши по таймлайн в After Effects и выберите Time> Enable Time Remapping.
Теперь можете отметить ключевые кадры по всему клипу, где бы вы хотели добиться ускорения. Добавьте по одному, а затем в другие места для замедления съёмки. Теперь сдвиньте ключевые кадры «для ускорения» ближе друг к другу, оставив участки нормальной скорости на прежнем расстоянии.
2. Сглаживание ключевых кадров
Выбрав все кадры, кликните по одному из них для сглаживания с зажатым Control-click. Это придаст плавности (значки станут круглыми, как точки) и ускорение сгладится.
3. Размытие в движении (Motion Blur)
Включите Frame Blending, щёлкнув по значку киноплёнки на временной шкале. Это добавит естественное размытие движения. Эффект виден по Enable Frame Blending на предварительном просмотре временной шкалы. (Как более крупный значок кадра над шкалой рядом с Motion Blur.)
4. Смените цветовое полотно
Можете добавить немного цветовых полос на вашем кадре. Это делается добавлением корректирующего слоя с эффектом Noise. Установите его значение около 4% с включённым цветовым шумом.
Дополнительный совет
WWW.IURAF.RU Уроки видеомонтажа в Adobe
Adobe After Effects. Урок 3
Панель Timeline.
Настройки, опции и параметры панели Timeline.
Задачи на этот урок:
1. Что нам предстоит изучить.
Для того, что бы Вы не имели сложностей в изучении программы Adobe After Effects нам необходимо изучить Рабочую среду программы. В связи со сложностью и широтой возможностей Adobe After Effects это может занять не один урок.
Но напрягите сердце мужеством. Мы рассмотрим подробно все основные опции и параметры, которыми нам предстоит пользоваться. Начнем с изучения на этом уроке панели Timeline, как основной рабочей панели.
2. Обзор панели TimeLine.
Панель Таймлайн разделим на 5 областей:
В областях выделим группы опций и параметров.
3. Группы опций и параметров панели TimeLine.
1. Заголовок панели, слева направо:
2. Заголовок слоев, слева направо:
ВНИМАНИЕ! Это строка заголовка слоев! Собственно опции и параметры изменяются в слоях, в рабочей области.
3. Рабочая область.
4. Графическая панель.
Без цифровых обозначений на рисунке:
Теперь рассмотрим подробно опции каждой области.
4. Опции области «Заголовок панели», слева направо:
Шесть опций клипа (все работают в режиме Вкл/Выкл)::
5. Опции области «Заголовок слоев», слева направо:
На картинках ниже я показываю не только Заголовок слоев, но и первый слой для примера установки опций и параметров.
Параметры выбора качества изображения слоя доступны также из главного меню: Layer/Quality, где становится доступным еще один параметр качества: Wireframe – так называемый каркас, отображает слой в виде рамки без содержимого. Рендеринг происходит намного быстрее, однако мы не видим картинки, а лишь их схематичное расположение.
Что бы опция включилась нужно нажать аналогичную кнопку в опциях клипа (см. выше). Если не выбран переключатель композиции Enable Frame Blending, расположенный в верхней части панели Timeline, то настройки смешения кадров не будут учитываться. Данный переключатель становится доступен для использования, когда мы изменяем скорость видео.
Сочетанием клавиш Shift+F4 можно скрывать/отображать этот столбец.
6. Рабочая область.
Какие компоненты есть в Рабочей области:
7. Графическая панель.
Сразу отметим, что это стандартный вид «Графической панели», нажмите кнопку «Graph Editor» в «Опциях панели» и панель изменится (будем изучать далее). Нажмите кнопку «Graph Editor» еще раз, чтобы вернуть стандартное представление Графической панели:
Теперь, сравнив возможности панели Таймлайн в Adobe Premiere и Timeline в Adobe After Effects Вы можете сравнить возможностях и сложность этих программ. (Это я все к тому, что Adobe After Effects младший брат Adobe Photoshop).
Time-stretching and time-remapping
Time-stretching, time-remapping, and the Timewarp effect are all useful for creating slow motion, fast motion, freeze frame, or other retiming results.
For information on the Timewarp effect, see Timewarp effect.
Time-stretch a layer
Speeding up or slowing down an entire layer by the same factor throughout is known as time-stretching. When you time-stretch a layer, the audio and the original frames in the footage (and all keyframes that belong to the layer) are redistributed along the new duration. Use this command only when you want the layer and all layer keyframes to change to the new duration.
If you time-stretch a layer so that the resulting frame rate is very different from the original frame rate, the quality of motion within the layer may suffer. For best results when time-remapping a layer, use the Timewarp effect.
Time-stretch a layer from a specific time
Holds the starting time of the layer at its current value and time-stretches the layer by moving its Out point.
Holds the layer at the position of the current-time indicator (also the frame displayed in the Composition panel), and time-stretches the layer by moving the In and Out points.
Holds the ending time of the layer at its current value and time-stretches the layer by moving its In point.
Time-stretch a layer to a specific time
To stretch the In point to the current time, press Ctrl (Windows) or Command (Mac OS) as you click the In time for the layer in the In column.
To stretch the Out point to the current time, press Ctrl (Windows) or Command (Mac OS) as you click the Out time for the layer in the Out column.
Time-stretch a layer but not its keyframes
When you time-stretch a layer, the positions of its keyframes stretch with it by default. You can circumvent this behavior by cutting and pasting keyframes.
Reverse the playback direction of a layer
When you reverse the direction at which a layer plays back, all keyframes for all properties on the selected layer also reverse order. The layer itself maintains its original In and Out points relative to the composition.
For best results, precompose the layer and then reverse the layer inside the precomposition. For more information on this process, see About precomposing and nesting.
Reverse keyframes without reversing layer playback
You can select and reverse keyframes across multiple layers and properties, but each set of keyframes for a property is reversed only within its original time range and not that of any other selected property. Markers in the Timeline panel are not reversed, so you may need to move markers after reversing keyframes.
Time-remapping
Time-remapping overview
You can expand, compress, play backward, or freeze a portion of the duration of a layer using a process known as time-remapping. For example, if you are using footage of a person walking, you can play footage of the person moving forward, and then play a few frames backward to make the person retreat, and then play forward again to have the person resume walking. Time-remapping is good for combinations of slow motion, fast motion, and reverse motion.
The Timewarp effect provides similar features with more control over some aspects of frame blending, but with additional limitations as a result of being applied as an effect.
When you apply time-remapping to a layer containing audio and video, the audio and video remain synchronized. You can remap audio files to gradually decrease or increase the pitch, play audio backward, or create a warbled or scratchy sound. Still-image layers cannot be time-remapped.
You can remap time in either the Layer panel or the Graph Editor. Remapping video in one panel displays the results in both. Each provides a different view of the layer duration:
The Layer panel provides a visual reference of the frames you change, as well as the frame number. The panel displays the current-time indicator and a remap-time marker, which you move to select the frame you want to play at the current time.
The Graph Editor provides a view of the changes you specify over time by marking your changes with keyframes and a graph like the one displayed for other layer properties.
When remapping time in the Graph Editor, use the values represented in the Time Remap graph to determine and control which frame of the movie plays at which point in time. Each Time Remap keyframe has a time value associated with it that corresponds to a specific frame in the layer; this value is represented vertically on the Time Remap value graph. When you enable time remapping for a layer, After Effects adds a Time Remap keyframe at the start and end points of the layer. These initial Time Remap keyframes have vertical time values equal to their horizontal position on the timeline.
By setting additional Time Remap keyframes, you can create complex motion results. Each time you add a Time Remap keyframe, you create another point at which you can change the speed or direction of playback. As you move the keyframe up or down in the value graph, you adjust which frame of the video is set to play at the current time. After Effects then interpolates intermediate frames and plays the footage forward or backward from that point to the next Time Remap keyframe. In the value graph, reading from left to right, an upward angle indicates forward playback, while a downward angle indicates reverse playback. The amount of the upward or downward angle corresponds to the speed of playback.
Similarly, the value that appears next to the Time Remap property name indicates which frame plays at the current time. As you drag a value graph marker up or down, this value changes accordingly and a Time Remap keyframe is set, if necessary. You can click this value and type a new one, or drag the value to adjust it.
The original duration of the source footage may no longer be valid when remapping time, because parts of the layer no longer play at the original rate. If necessary, set a new duration for the layer before you remap time.
As with other layer properties, you can view the values of the Time Remap graph as either a value graph or a speed graph.
If you remap time and the resulting frame rate is very different from the original, the quality of motion within the layer may suffer. Apply frame blending to improve time remapping for slow motion or fast motion.
Use the information shown in the Info panel to guide you as you work with time-remapping. The ratio given in the units of seconds/sec indicates the current speed of playback—the number of seconds of the original layer being played for each second after time-remapping.
Time-remap a layer
You can time-remap all or part of a layer to create many different results, such as freeze-frame or slow-motion results. (See Time-remapping.)
Frame blending что это
5.3.2. Панель инструментов окна Timeline
Перечислим кнопки, которые находятся на панели инструментов ( Timeline window buttons ) в верхней части окна Timeline (Монтаж), позволяют управлять включением и выключением различных режимов редактирования слоев и опций их вставки в композиции (рис. 5.16):
Панель инструментов содержит пять кнопок, управляющих всеми слоями сразу. В столбце Switches/Modes (Переключатели/Режимы), находящемся под ней, можно задать те же самые параметры для каждого индивидуального слоя в отдельности (рис. 5.17). Перечислим эти режимы (слева направо):
Рис. 5.17. Переключатели отдельных слоев в окне Timeline
Выключатели слоя (Аудио / Видео / Соло / Запирание)
Панель с выключателями, позволяющими временно скрыть слой из композиции, либо, напротив, включить его. Если возле слоя имеется пиктограмма в виде глаза (и/или акустического динамика), то видео (и/или звук), составляющие слой, включаются в состав композиции. Если снять данные переключатели для каких-либо слоев, то это их временно изымет из фильма, что очень удобно при монтаже сложных композиций, а также важно для правки определенных слоев (чтобы остальные слои не мешали монтажу в окне Composition ).
Рис. 5.18. Выключатели слоев в окне Timeline: Аудио / Видео / Соло / Запирание
Пиктограмма в виде окружности Solo (Соло) позволяет временно выключить все слои, кроме тех, для которых установлен данный атрибут. Самая правая из пиктограмм с изображением замка временно (до ее последующего снятия) запрещает любое редактирование данного слоя.
В верхней части окна Timeline (Монтаж), над рассмотренной группой переключателей, находится строка с таймкодом текущего кадра (current time), которая представляет его номер в соответствии с выбранной системой (см. урок 1). В скобках отображается текущая частота кадров. При щелчке на номере кадра выводится диалоговое окно, при помощи которого можно численно задать его новое значение, т. е. перейти к желаемому кадру композиции, введя его вручную с клавиатуры.
При помощи команды Columns (Столбцы) меню окна Timeline (Монтаж) можно вызвать на экран или, наоборот, скрыть, столбцы со вспомогательной информацией (рис. 5.19). Многие из них будут разобраны ниже, когда мы обратимся к изучению конкретных задач монтажа в After Effects.
Рис. 5.19. Скрыть или вызвать вспомогательные столбцы можно при помощи меню окна Timeline
Перечислим столбцы, которые могут присутствовать в окне Timeline (Монтаж):
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.