User Manual

Pro Tools Reference Guide20
Metadata
Metadata is used to describe the following:
• Information embedded in a media file. This may
include scene, take, sample rate, bit depth, exter-
nal clip names, the name of the videotape from
which the media file was captured, and even
timecode values.
• Information embedded in Pro Tools sessions or
other sequences, including what files are used,
where they appear in a timeline, and automation.
• For AAF or OMF sequences, metadata also in-
cludes information embedded in unrendered Au-
dioSuite™ effects (such as real-time EQ) for
Media Composer. Pro Tools skips unrendered
effects on import. Rendered effects are media
files that can be imported into Pro Tools.
• For AAF or OMF sequences, information about
automation (clip-based gain or keyframe gain).
AAF, OMF, and MXF Basics
AAF and OMF files are mechanisms for storing
and retrieving media files and metadata so that
projects can be freely exchanged between different
applications and platforms. MXF is a media file
format that can be used with AAF (but not OMF)
files.
Media data and metadata enable an application that
receives AAF and OMF sequence files (such as
Pro Tools) to automatically and quickly reassem-
ble the composition. A simple metaphor for this
approach is that media data files are the pieces of a
puzzle and metadata is the set of instructions for
assembling the puzzle.
In the simplest case, only an AAF or OMF se-
quence is exchanged. If this sequence points to ex-
isting media files, the size of the sequence file is
relatively small and the export/import process is
relatively fast.
AAF and OMF sequences can also have media
data embedded in them. This creates a single,
larger file that is slower to export and import, but
which may be easier to manage than thousands of
files stored on different volumes.
AAF
AAF is a sequence file format. AAF sequences are
the best way to exchange projects and maintain
valuable metadata. An AAF sequence can refer to
OMF or MXF media files, or have OMF and MXF
media files embedded within them. There is no
such thing as an AAF audio or video media file.
Pro Tools will import, play back, and export an
AAF sequence that either links to media files or
has audio embedded within it.
When you import an AAF sequence with embed-
ded audio into Pro Tools, the audio will be
extracted into mono tracks using the current ses-
sion’s audio file format.