To start a preview of video and audio, do any of the following:
Though it is common to speak of rendering as if this term only applies to final output, the processes of creating previews for the Footage, Layer, and Composition panels are also kinds of rendering.
You can preview all or part of your composition as you work, without rendering to final output. Many of the controls for previewing are in the Preview panel.
After Effects allocates RAM to play video and audio in the Timeline, Layer, or Footage panel at real-time speed. The number of frames that can be stored for real-time playback depends on the amount of RAM available and the settings in the Preview panel.
The default preview behavior is configured to produce a preview that represents a real-time playback. When you press spacebar (the default keyboard shortcut), After Effects starts a preview with audio, and caches frames until the available RAM is filled.
To start a preview of video and audio, do any of the following:
You can configure the Preview options to suit your working style. Controls in the Preview panel allow you to configure preview behaviors for each keyboard shortcut (Spacebar, Shift+spacebar, Numpad-0,Shift+Numpad-0, Numpad-, or Option/Alt+Numpad-) audio, looping, caching, range, and layer controls.
To configure settings for Preview, do the following:
The Preview panel is open by default in most workspaces within After Effects. However, if the Preview panel is closed, select Window > Preview to open it.
In the Preview panel, you can modify the following settings to configure Preview behavior:
Choose a keyboard shortcut to play/stop a preview: Spacebar, Shift+spacebar, Numpad-0, Shift+Numpad-0, or Option/Alt+Numpad-0 . The Preview behavior depends on the settings specified for the currently selected keyboard shortcut.
Restore default preview settings for all Shortcut keys.
To restore preview settings for all keyboard shortcuts to closely match their behaviors in previous versions (After Effects CC 2014 and earlier), hold the Option (Mac OS) or Alt (Windows) key, and click the Reset button.
Include Video: When enabled, the preview plays video.
Include Audio: When enabled, the preview plays audio.
Include Overlays and Layer Controls: When enabled, the preview shows overlays (for example, grids and guides) and layer controls for selected layers as defined in the View > View Options dialog box. This can be enabled regardless of whether Include Video is enabled.
Viewer panel overlays include guide lines, safe margins, grids, and 3D reference axes. To choose which overlays to show for the current viewer, open the Choose Grid and Guide options menu at the bottom of the viewer panel.
While a preview is playing back, you can dynamically show or hide layer controls using: Cmd + Shift + H (Mac OS) or Control + Shift + H (Windows).
Loop: Specify if you want the Preview to play in a loop.
Note: Showing or hiding layer controls during a preview does not affect the state of the Layer controls option in the Preview panel.
Note: You cannot simultaneously disable all the three Include buttons. At least one button must remain enabled. When you disable the third button, one of the other buttons is enabled.
Cache Before Playback: When you enable this option, After Effects caches frames before starting playback. This option is not enabled by default for any of the preview shortcuts. If you Option- (Mac OS) or Alt- (Windows) click the Reset button in the Preview panel, Cache Before Playback is enabled for Numpad-0.
Defines the range of frames that are previewed:
Play Around Current Time: When you start a preview with Play Around Current Time enabled, the preroll value is subtracted from the current time, the postroll value is added to the current time, and the frames in-between are previewed.
To set the preroll and postroll values:
Specify a Frame Rate for the preview. Select Auto if you want the preview and composition frame rates to be equal.
Select the number of frames you want to skip while previewing to improve playback performance.
Specify preview resolution. Value specified in the Resolution drop-down overrides resolution setting of the composition.
You can stop a preview using any of the following:
The following actions also cause After Effects to stop a preview:
The Play/Stop button in the Preview panel and Composition > Preview > Play Current Preview are linked to the shortcut currently displayed in the Preview panel. Using these actions to stop a preview has the same result as pressing the currently displayed keyboard shortcut.
The following are the default preview settings for each of the preview keyboard shortcuts:
Shift + Spacebar
When the Spacebar is used to stop a preview:
When the Shift + Spacebar is used to stop a preview:
When the Numpad-0 is used to stop a preview:
Shift + Numpad-0
Alt + Numpad-0
When the Shift+Numpad-0 is used to stop a preview:
When the Numpad+0 is used to stop a preview:
When the Alt+Numpad-0 is used to stop a preview:
When you preview only audio, it plays immediately at real-time speed, unless you’ve applied audio effects other than Stereo Mixer, in which case you may have to wait for audio to render before it plays.
Set the sample rate for audio for the entire project in the Project Settings dialog box (File > Project Settings).
The Audio Hardware and Audio Output Mapping preferences determine the behavior of audio previews. The output module settings determine the quality of audio in final output. In the Audio Hardware pane of the Preferences dialog box (Edit > Preferences > Audio Hardware), you can select the device class, map the default output and change the settings, and set the latency.
If you stop moving the current-time indicator (CTI) with the mouse button depressed while scrubbing with audio, a short section of audio loops.
To manually preview (scrub) only the frames that are already rendered and cached into the RAM cache, press Caps Lock before dragging the current-time indicator (CTI). This prevents After Effects from trying to render other frames when you drag over or past them. This technique is useful when you want to manually preview some frames that you rendered using preview settings that used an option to skip every other frame.
During previews, the Audio panel volume unit (VU) meter actively displays audio volume levels. At the top of the VU meter, signals indicate when the audio is clipping—a distortion that occurs when the audio signal exceeds the maximum level that the audio device allows.
To view the VU meter and levels controls in more detail, increase the height of the Audio panel.
Choose Options in the Audio panel menu to specify the following options:
Choose whether to display audio levels in decibels or in percentages. 100% equals 0 decibels (0 dB).
The minimum audio level to display in the Audio panel.
Use the Resolution/Down Sample Factor settings menu which is one of the simplest and most influential of the preview settings controls. Choose a value other than Full from this menu to see all previews at a lower resolution.
To turn pixel-aspect ratio correction on or off for previews, click the Toggle Pixel Aspect Ratio Correction button at the bottom of the panel. The quality of the pixel aspect ratio correction is determined by the Zoom Quality preference. (See Viewer Quality preferences.)
Select Show Rendering Progress In Info Panel And Flowchart (Edit > Preferences > Display (Windows) or After Effects > Preferences > Display (Mac OS)) to see additional information in the Info panel or the project Flowchart panel during rendering, either for previews or for final output.
The most basic way of previewing frames is to manually preview by moving or dragging the current-time indicator (CTI).
The time ruler visually represents the time dimension of a composition, a layer, or a footage item. In a Layer or Footage panel, the time ruler appears near the bottom of the panel. For a Composition panel, the time ruler appears in the corresponding Timeline panel. The time rulers in different panels represent different durations. The time ruler in a Layer or Footage panel represents the duration of the contents of that panel; the time ruler in the Timeline panel represents the duration of the entire composition.
On a time ruler, the current-time indicator indicates the frame you are viewing or modifying.
To go forward or backward one frame, click the Next Frame or Previous Frame button in the Preview panel, or press Page Down or Page Up.
To go forward or backward ten frames, Shift-click the Next Frame or Previous Frame button, or press Shift+Page Down or Shift+Page Up.
To go forward a specific period of time or number of frames, click the current-time display, and then enter the plus sign (+) followed by the timecode or number of frames to advance. For example, enter +20 to go forward 20 frames or 1:00 to go forward one second. Precede the value by the minus sign (-) to go backward. For example, enter +-20 to go backward 20 frames or +-1:00 to go backward one second.
To go to the first or last frame, click the First Frame or Last Frame button in the Preview panel, or press Home or End.
To go to the first or last frame of the work area, press Shift+Home or Shift+End.
To go to a specific frame, click in the time ruler; click the current-time display in the Footage, Layer, Composition, or Timeline panel; or press Alt+Shift+J (Windows) or Option+Shift+J (Mac OS). You can also drag the current-time display in the Timeline panel to modify the value.
Shift-drag the current-time indicator to snap to keyframes, markers, In and Out points, the beginning or end of the composition, or the beginning or end of the work area.
If you scrub the CTI while a preview is playing, preview stops. To scrub the CTI without stopping a preview, hold Option/Alt while scrubbing.
When you click the Time Navigator in the Timeline panel, the Info panel shows the times of the beginning and end of the Time Navigator duration.
For additional ways to zoom and scroll in time using the mouse scroll wheel, see Scroll or zoom with the mouse wheel.
When zoomed in time, press D to center the time graph on the current time.
Designating a viewer as the default panel to preview is especially useful when you have a Composition viewer that represents your final output and you always want to preview that viewer, even when you’re changing settings in other panels.
The panel that’s set to always preview appears frontmost for the duration of the preview.
Click the Always Preview This View button in the lower-left corner of the panel.
The Primary Viewer button is located next to the Always Preview This View button in the lower left of the Composition, Layer, and Footage viewer panels.
Primary Viewer functions similarly to Always Preview This View, except that Primary Viewer only defines which viewer or view is used for audio and external video preview.
When multiple views are open, previews use the frontmost composition view for 2D compositions and the Active Camera view for 3D compositions. To turn off the Active Camera, deselect Previews Favor Active Camera in the Preview panel menu.
After Effects provides several options for previewing that make various tradeoffs between speed and fidelity.
Each preview mode provides a different balance between quality and speed for playback and for updating of images during interactions, such as when you drag a layer in the Composition panel or modifying a property value in the Timeline panel.
Draft 3D and Live Update modes apply to all views of a composition.
Disables lights, shadows, and depth-of-field blur for cameras. To turn Draft 3D mode on or off, click the Draft 3D button at the top of the Timeline panel.
Updates images in the Composition or Layer panel during interactions. When Live Update is deselected, After Effects displays wireframe representations during interactions.
To temporarily toggle Live Update mode, hold Alt (Windows) or Option (Mac OS) while dragging to move a layer, modify a property value, or move the current-time indicator (CTI).
To prevent After Effects from updating images in the Footage, Layer, and Composition panels, press Caps Lock. When you make a change that would otherwise appear in a panel, After Effects adds a red bar at the bottom of the panel with a text reminder that image refresh is disabled. After Effects continues to update panel controls such as motion paths, anchor points, and mask outlines as you move them. To resume panel updates and display all changes, press Caps Lock again. Pressing Caps Lock is a good way to prevent views from being refreshed for each frame during rendering for final output.
When you are using OpenGL to render previews and are previewing on a video monitor, the preview shown on the video monitor doesn’t update as you interact with elements of your composition until you have released the mouse at the end of an interaction. (See Preview on an external video monitor.)
The Fast Previews options range from higher quality but slower performance (Off), to lower quality but higher performance (Wireframe).
Off (Final Quality)
Fast Previews is off. Use this mode when previewing the final quality of your composition.
Attempts to downsample footage while dragging a layer or scrubbing a property value. For the ray-traced 3D compositions, Adaptive Resolution reduces the ray-tracing quality based on the current adaptive resolution:
You can change the adaptive resolution limit in Edit > Preferences > Previews (Windows) or Premiere Pro > Preferences > Previews (Mac OS).
Available in ray-traced 3D compositions only. This option reduces the ray-tracing quality (number of rays fired by the ray tracer) to 1.
When laying out a complex scene, or if you are working in a ray-traced 3D composition, you can use Fast Draft mode for previewing. In ray-traced 3D compositions, Fast draft mode renders beveled, extruded, and curved 3D layers. When previewing, the scene is downsampled to speed up the loading of textures to the GPU. In Fast Draft mode, each frame of video is still read into the renderer as needed. The downsample factor is set at 1/4 resolution, and effects and track mattes are on.
Useful for setting up and previewing complex compositions.
Changing the Fast Previews mode to match your workflow is important, especially when working with ray-traced 3D compositions.
Off (Final Quality)
Ctrl+Alt+1 (Windows) / Cmd+Option+1 (Mac OS)
Ctrl+Alt+2 (Windows) / Cmd+Option+2 (Mac OS)
Ctrl+Alt+3 (Windows) / Cmd+Option+3 (Mac OS)
Ctrl+Alt+4 (Windows) / Cmd+Option+4 (Mac OS)
Ctrl+Alt+5 (Windows) / Cmd+Option+5 (Mac OS)
In the Previews preferences category, you can choose the quality and speed of color management and zoom operations used in previews.
From the Zoom Quality or Color Management Quality menu, choose one of the following:
The Zoom Quality preference affects the quality of scaling performed for pixel aspect ratio correction in the Composition and Layer panels.
When the Show Channel menu is set to an option that shows straight colors (RGB Straight, Alpha Overlay, or Alpha Boundary), the Viewer Quality preference is ignored, and the preview is created as if the Viewer Quality settings were Faster.
The region of interest (ROI) is the area of the composition, layer, or footage item that is rendered for previews. Create a smaller region of interest to use less processing power and memory when previewing, thereby improving interaction speed and increasing preview duration.
By default, changing the region of interest does not affect file output. You can change the size of your composition and select what portion is rendered by cropping to the region of interest.
When the region of interest is selected, the Info panel displays the horizontal and vertical distances of the top (T), left (L), bottom (B), and right (R) edges of the region from the upper-left corner of the composition.
To start over with the marquee tool, hold down Alt (Windows) or Option (Mac OS) and click the Region Of Interest button.
To create the equivalent of a region of interest for a single layer, you can draw a temporary mask around the part of the layer that you are working with. The area outside the mask is not rendered. This can make working with a small portion of a large layer much faster. Be careful, though, since not rendering the pixels outside the mask can change the composition’s appearance significantly. (See Creating masks.)
The work area is the part of the duration of a composition that is rendered for previews or final output. In the Timeline panel, the work area appears in a lighter shade of gray.
To expand the work area to the size of the composition, double-click the center of the work area bar.
When you want to compare one view to another in a Composition, Layer, or Footage panel, take a snapshot. For example, you may want to compare two frames at different times in a movie.
Snapshots taken in one kind of panel can be displayed in another kind. For example, you can take a snapshot of a Layer panel and display the snapshot in a Composition or Footage panel. Displaying a snapshot does not replace the content of the panel. If the snapshot has a different size or aspect ratio than the panel in which you display it, the snapshot is resized to fit the current view.
Snapshots are for reference only and do not become part of the layer, composition, or rendered movie.
A sound is generated when you take a snapshot.
You can preview the contents of your Layer, Footage, or Composition panel on an external video monitor. Previewing on a video monitor requires additional hardware, such as a video capture card or a FireWire port.
Previews can be displayed on a second monitor connected to your video display card , such as via DVI, DisplayPort, or HDMI. If you are using a video capture card to connect an external video monitor, install the appropriate drivers and connect the monitor to view previews. If you are using a FireWire port, first connect a digital camcorder or similar device to the port; then connect the video monitor to the device. For more information on setting up FireWire previews, see the documentation for your digital camcorder, VCR, or other devices.
Choose Edit > Preferences > Video Preview (Windows) or After Effects > Preferences > Video Preview (Mac OS).
To enable video output to an external device, choose from the following options:
Choose Disable video output when in the Background option to prevent video frames from being sent to the external monitor when After Effects is not the foreground application.
Choose the Video preview during render queue output option to send video frames to the external monitor when After Effects is rendering frames in the render queue.
The video preview sent to an external monitor using Mercury Transmit is color-managed (treating the external video preview monitor as an HDTV Rec. 709 device). For more information, see the Video preview using Mercury Transmit article.
The Wireframe preview mode does not preview at all to the video preview monitor. (See Preview modes and Choose a working color space and enable color management.)