Preview
Window

Specific to the Timeline Editing interface, the Preview Window is
a dedicated screen for previewing individual asset clip (from Timeline Asset Bin) or movie scene (from Timeline strip). There are 4 video buttons (pause, play,
previous frame, and next frame) and a frame scrubber
lined along the bottom side of this window. They are used for playback
and frame search of a movie clip or scene. On the top side of the
window there is a frame counter showing both the current
and total frame numbers of the previewed clip or scene. If there is
a scene length
symbol present next to the frame counter, it means the length of the
current scene had been modified. You can reset the scene to its original
length or make further changes to it in Scene Composition mode.
The play button is to play a clip or scene from the beginning to end.
The pause button is to temporarily stop the play progress. You
use previous and next buttons to advance one frame at a time in respective directions. You use the frame scrubber to locate
a particular part of a clip or scene more quickly.
To Preview a Clip (from Asset Bin)
you simply drag a thumbnail from the Assets Bin and drop it into Preview Window to get it loaded.
The first frame of that clip will show in the Window. Now use the video buttons and frame scrubber to examine the clip.
To Preview a Scene (from Timeline)
you can
either a.
click on the thumbnail of a scene in Timeline to have it loaded in Preview window
or, b. drag
a thumbnail from the Timeline and drop it in Preview window to have it loaded. Now use the
video buttons and frame scrubber to examine the scene.
To Switch from TE mode to SC Mode
When
a 'scene' (not a 'clip') is loaded in Preview Window, the title text PREVIEW will change itself into a button. You roll your mouse over it the text now says COMPOSE SCENE. This means the button is live. Clicking on it will switch you from TE mode
to SC mode changing the Preview Window into Compose Window. This 'switcher' UI is not available when a 'clip' (from Asset bin) is loaded in the Preview Window.
To Add a Previewing Clip or Scene
to Timeline
To add a clip or scene from Preview Window to your movie, you simply drag the screen picture from the Preview Window
to a desired spot in your Timeline. You'd see a ghostly thumbnail of the respective clip or scene being grabbed from Preview Window into Timeline strip.