4.5

148Compressor User Guide
Set a poster frame in Compressor
The poster frame is a still image that represents a video or audio media file or a
podcast chapter.
Note: When viewing the output file in Apple TV Home Videos, if no poster frame is set,
Apple TV Home Videos automatically uses the frame 10 seconds from the movie’s first
frame as the poster frame.
Set the poster frame for a job
1. In the Compressor batch area, select the job that contains the source file that you want
to set a poster frame in.
Tip: To select the job, rather than an output row under the job, click the source
filename at the top of the job area.
2. In the preview area, position the timeline playhead at the frame you want to be the
poster frame.
3. In the preview area, click the Marker pop-up menu, then choose Set Poster Frame.
A poster frame marker appears in the timeline.
Go to the poster frame
• In the Compressor preview area, click the Marker pop-up menu, then choose Go to
Poster Frame.
Remove the poster frame
• In the preview area, click the Marker pop-up menu, then choose Clear Poster Frame.
Add markers using Compressor
A marker flags a specific timing location in a source file. You can use Compressor to
append a marker with editing notes or other descriptive information. Additionally, when you
output the source file to an H.264, MPEG-2, or MPEG-4 video format, each marker forces
the creation of an I-frame. Added I-frames improve compression quality, but can increase
overall file size. Compressor can create the following types of markers:
• Chapter markers: Generate named index points and thumbnail images for DVDs,
QuickTime movies, or video podcasts. You can also assign a URL to a chapter marker to
have that URL appear during playback of a podcast. Chapter markers are also included
in submissions to the iTunes Store as part of an iTunes Store package. Chapter markers
appear orange in the Compressor preview area.
• Compression markers: Generate an I-frame, but do not generate thumbnails, chapter-
track entries, or other metadata. Add them to a video if a section appears to have lower
image quality than the surrounding frames. Compression markers appear blue in the
Compressor preview area.
• Edit markers: Function identically to compression markers. They are commonly used by
compression artists to force an I-frame at an edit point to ensure higher image quality
at that moment in the video. Edit markers appear red in the Compressor preview area.