4.2

included in submissions to the iTunes
Store as part of an .
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/cut 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/cut markers appear red in the
iTunes Store Package