Region of interest (roi), Work area, During the brainstorm session. (see – Adobe After Effects CS4 User Manual
Page 207
201
USING AFTER EFFECTS CS4
Views and previews
Last updated 12/21/2009
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.
Note: 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
More Help topics
Region of interest (ROI)
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 RAM 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.
Note: 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 top-left corner of the composition.
•
To draw a region of interest, click the Region Of Interest button
at the bottom of the Composition, Layer, or
Footage panel, and then drag to select a viewable area of the panel.
To start over with the marquee tool, hold down Alt (Windows) or Option (Mac OS) and click the Region Of Interest
button.
•
To switch between using the region of interest and using the full composition, layer, or footage frame, click the
Region Of Interest button.
•
To move or resize the region of interest, drag its edges or handles. Shift-drag a corner handle to resize while
preserving aspect ratio.
•
To crop the composition to the region of interest, choose Composition
> Crop Comp To Region Of Interest.
•
To crop the output to the region of interest, choose Use Region Of Interest in the Crop section of the Output
Module Settings dialog box. (See “
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 of the mask will not be rendered. This can make working with
a small portion of a large layer much faster. Be careful, though, since not rendering the pixels outside of the mask can
change the composition’s appearance significantly. (See “
Work area
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 set the work area start time or end time to the current time, press B (begin) or N (end), respectively.
•
To set the work area, move the start and end work area markers in the time ruler.