Adobe PREMIERE 5 User Manual page 310

302 CHAPTER 11
Producing Final Video
Setting keyframes
Some codecs provide an additional degree of control over file size and picture quality by using
compression keyframes, which act as starting points for temporal compression (see "Temporal
compression" on page 349). You can set keyframes at an interval you specify or at markers you
set in the Timeline. If the codec you specified doesn't support keyframes, keyframe options
aren't available.
To specify keyframe options:
Do one of the following:
1
To specify keyframe options for recording on videotape as the Timeline plays, choose
•
Project > Settings > Keyframe and Rendering Options.
To specify keyframe options as you export a video file, choose File > Export > Movie, click
•
Settings, make sure the File Type is the one you want, and choose Keyframe and Rendering
Options from the menu at the top of the Export Movie Settings dialog box.
Do one of the following:
2
Select Keyframe Every _ Frames and type the number of frames after which the codec will
•
create a keyframe when exporting video.
Select Frames Only At Markers to create keyframes only where markers exist on the Timeline.
•
Specify the following options as needed and then click OK:
3
Select Add Keyframes At Markers to also create a keyframe at each marker. For this to work,
•
markers must exist in the time ruler in the Timeline (see "Using markers" on page 153).
Select At Edits to also create a keyframe at the beginning of each clip in the Timeline.
•
Note: Some codecs do not provide control over keyframes. In such codecs, the options in steps 2
and 3 will not be available.