TITLE
    Final Cut Pro 1.0: Subframe Audio Editing
Article ID:
Created:
Modified: 		60268
4/15/99
7/23/99
TOPIC

    You can apply audio keyframes to part of a frame and adjust the position of an audio frame relative to a video frame. These adjustments, called "subframe audio editing," are useful for removing a "pop" in the audio (using keyframes) or synchronizing sound and video in tiny increments (using a slip edit).

DISCUSSION

    Audio and Video may sometimes be out of sync due to a phenomenon called subframe slipping.

    Audio and video do not share the same unit of measure, with video being captured in fields or frames and audio being captured in samples.

    The following steps appear in the Final Cut Pro user's guide and may be used to sync audio and video tracks to resolve subframe slipping.

    To adjust audio keyframes:
      1. Open the clip in the Viewer and click the Audio tab.
      2. Using the Zoom tool (magnifying glass) in the Tool Palette, zoom in as far as possible. The wide playhead bar in the Viewer represents one video frame at full magnification.
      3. Move the playhead to the exact location in the audio waveform you want.
      4. Click the Add Keyframe button in the Viewer.
      5. Adjust the Level (sound volume) or Pan/Spread (sound placement) slider as desired.
      6. To make further changes, move the playhead to a new position and adjust the sliders again.

    To perform an audio subframe slip edit:
      1. Open a clip with both video and audio in the Viewer and click the Audio tab.
      2. Using the Zoom tool (magnifying glass) in the Tool Palette, zoom in as far as possible. The wide playhead bar in the Viewer represents one video frame at full magnification.
      3. Press the Shift key and position the left edge of the playhead where you want to set an In or Out point, using the audio waveform as your guide.
      4. Click the Mark In or Mark Out button. The program automatically slips the audio by a subframe amount to the boundary of the previous whole frame.

    When capturing a large amount of data, using the recommended "setup" or better is preferred. For example, capturing audio and video to separate drive arrays would be the most preferred method for high-end projects. Disabling audio compression and reducing the "resolution" of the audio being captured may also help alleviate "bandwidth" issues that can cause timing delays.

    If timing issues continue to occur, resetting the camera or deck or restarting the computer should resolve the issue.

    Consult the Final Cut Pro user's guide for more information on recommended configurations.

Document Information
Product Area: Apple Software
Category: Final Cut Pro
Sub Category: General Topics

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