Apple Final Cut Pro 7 - Manual (Page 683)

Viewing an Audio Clip at Single-Frame Resolution
When you’re editing an audio clip in the Viewer, you can zoom in so far that the playhead
is the width of a single video frame on the waveform. You can use this single-frame view,
along with the subframe scrubbing function in Final Cut Pro, to match the beats of musical
clips you edit together; or you can use it to set subframe keyframes to eliminate pops or
clicks that occur at the audio edit points you’ve chosen. If you do not hear audio from
the monitoring speakers while scrubbing, you may need to turn up the volume, or you
may have audio turned off (see
“Turning Off the Audio Scrubbing Sounds” ).
Subframe Synchronization of Audio and Video
When you’re synchronizing audio and video, audio that’s as little as 300 samples off
perfect sync can be noticeable. For this reason, Final Cut Pro allows you to resynchronize
your audio in increments of 1/100 of a frame. There are several cases in which this will
come in handy:
• When editing music clips together, it’s essential that you edit them together precisely
on the beat. Even a subtle offset can upset the rhythm.
• Video and audio that were recorded from separate sources and resynchronized on tape
may be subtly out of sync.
• Audio that was recorded with a microphone far away from the audio source might
have an offset between the video and audio, because sound moves through the air
more slowly than light.
To navigate through a clip by subframe units
1 Open a clip in the Viewer.
2 Hold down the Shift key while dragging the playhead within the duration of a single
video frame.
This allows you to move the playhead in increments of 1/100 of a frame. When you set
a new edit point in the clip, the clip’s audio item slips a fraction of a frame, establishing
a new sync relationship between the video and audio items.
To slip an audio clip item by subframe units
1 Open a clip with both video and audio items in the Viewer, then click the audio tab.
683 Chapter 43 Audio Editing Basics