Glossary: M
M & E track
The common designation for a single sound track containing music and sound effects but not dialog.
magnetic track
A sound track recorded on magnetic sound recording film.
mark IN/OUT
1.  The process of entering the start and end timecodes for a clip to be edited into a sequence.
2.  The process of marking or logging timecode numbers to define clips during a logging, recording, or digitizing session.
See also IN point, OUT point.
mask
1.  In film, a border placed over an image with a 3:4 aspect ratio to create the look of an another aspect ratio, such as wide-screen.
2.  See alpha channel.
master
The tape resulting from editing. The finished program.
master clip
In the bin, the media object that refers to the media files recorded or digitized from tape or other sources.
See also clip, subclip.
master shot
The shot that serves as the basic scene, and into which all cutaways and close-ups will be inserted during editing. A master shot is often a wide shot showing all characters and action in the scene.
master/slave
A video-editing process in which one or more decks (the slaves) are set to imitate the actions of another deck (the master).
matchback
The process allowing you to generate a film cut list from a 30-fps video project that uses film as the source material.
matchback conversion
The conversion from film to video frame rates.
match-frame edit
An edit in which the last frame of the outgoing clip is in sync with the first frame of the incoming clip, such that the incoming clip is an extension of the outgoing clip.
matte key
A video effect comprised of three components: the background video, the foreground video, and the matte or alpha channel (black and white or grayscale silhouette) that allows one portion of the image to be superimposed on the other.
media
The video, audio, graphics, and rendered effects that can be combined to form a sequence or presentation.
media data
Data from a media source. Media data can be:
1.  Analog data: film frames, Nagra tape audio, or videotape video and audio.
2.  Digital data: either data that was recorded or digitized such as video frame data and audio samples, or data created in digital form such as title graphics, DAT recordings, or animation frames.
media files
Files containing the compressed digital audio and video data needed to play Avid clips and sequences.
See also clip, compression.
media sample data
See safe color limiting.
megahertz (MHz)
One million cycles per second.
See also hertz (Hz), kilohertz (kHz).
MIDI
Musical Instrument Digital Interface. A standard protocol that allows a user to control electronic music equipment from a PC.
MII format
A component videotape format created by Panasonic in an effort to compete with Sony Betacam. MII is an extension of the VHS consumer format as Sony Betacam is an extension of the Betamax home video technology.
mix
1.  A transition from one video source to another in a switcher.
2.  The product of a recording session in which several separate sound tracks are combined through a mixing console in mono or stereo.
mixdown audio
The process that allows the user to combine several tracks of audio onto a single track.
monitor
1.  In video, a picture tube and associated circuitry without tuner or audio sections. The monitor includes the display of source media, clips, and sequences.
In Avid products, virtual monitors are displayed on the screen in which source media, clips, and sequences can be edited.
2.  In audio, to monitor specific audio tracks and channels, or another name for the speakers through which sound is heard.
MOS
The term used for silent shooting. From the pseudo-German, "Mit Out Sprechen"— without talking.
motion effect
An effect that speeds up or slows down the presentation of media in a track.
motion tracking
The process of generating position information that describes motion in a clip, for example, the changing position of a moving vehicle. You use motion tracking data to control the movement of effects.
See also stabilization.
MU/FX or MUFX
See M & E track.
multicamera
A production or scene that is shot and recorded from more than one camera simultaneously.
multiple B-roll
A duplicate of the original source tape, created so that overlays can be merged onto one source tape.
multitrack
A magnetic tape or film recorder capable of recording more than one track at a time.

Some features described in Help are available only in Avid Xpress Pro or Avid Xpress DV. For more information about Avid Free DV go to
www.avid.com.