Apple Compressor 2 - Manual (Page 219)

Chapter 16 Using the Preview Window 219
Transcoding a Portion of the Clip With the Preview Window
You can use the Preview window to set In and Out points to transcode only a portion
of your media file rather than transcoding the whole thing.
To designate a portion of your media file for transcoding:
1 Open the Preview window.
2 Choose a clip from the Batch Item pop-up menu or click the Batch Item selection
buttons until the clip appears in the pop-up menu.
3 Do one of the following:
 Drag the In point to the appropriate location.
 Drag the playhead to where you want transcoding to begin and click the
Set In Point button.
4 Do one of the following:
 Drag the Out point to the appropriate location.
 Drag the playhead to where you want transcoding to end and click the
Set Out Point button.
The only segment of the media file that will be transcoded is between the two points
that you set. The rest of the clip will not be transcoded.
In point Out point
Playhead