Preview media
Once you have imported your media files from Microsoft Expression Encoder, you can use tools to play your files before you begin trimming, cropping, or adding additional clips.
In the Media Content panel, select the clip that you want to preview.
To preview the clip, do one of the following:
To start or pause playback, click Play/Pause.
To advance to or go back to the nearest marker, click either Go to next marker
or Go to previous marker 
. If there are no remaining markers, the playhead moves to either the end or the beginning of the clip. To advance or go back by a single frame, click either Next frame
or Previous frame 
. To scroll through the media, drag the playhead. The number of frames that you cover while dragging the playhead depends on the zoom level of the Timeline. To zoom the Timeline, click Zoom in
or Zoom out 
, or drag the slider between the two buttons.
