mvGetTrackLength(3dm)mvGetTrackLength(3dm)NAME
mvGetTrackLength, mvGetScannedLength, mvGetTrackMedium, mvGetTrackId,
mvGetTrackMovie, mvGetTrackDisplayWidth, mvSetTrackDisplayWidth,
mvGetTrackDisplayHeight, mvSetTrackDisplayHeight, mvSetTrackSMPTEStart,
mvGetTrackSMPTEStart - get and set the properties of a track
SYNOPSIS
#include <dmedia/moviefile.h>
MVframe mvGetTrackLength( MVid track )
MVframe mvGetScannedLength( MVid track )
DMmedium mvGetTrackMedium( MVid track )
int mvGetTrackId( MVid track )
MVid mvGetTrackMovie( MVid track )
int mvGetTrackDisplayWidth( MVid track )
DMstatus mvSetTrackDisplayWidth( MVid track, int width )
int mvGetTrackDisplayHeight( MVid track )
DMstatus mvSetTrackDisplayHeight( MVid track, int height )
DMstatus mvSetTrackSMPTEStart( MVid movie, const char* start_time )
const char* mvGetTrackSMPTEStart( MVid track )
DESCRIPTION
All of the data accessed by these functions can also be accessed using
mvGetParams(3dm) and mvSetParams(3dm).
mvGetTrackLength returns the number of frames playable at the frame rate
of a track.
For some compression schemes, MPEG in particular, a movie file can be
opened in one of two modes, with prescan or without prescan. Movies
opened without prescan do not have a defined length for their tracks.
mvGetScannedLength provides a way to get at the length currently known to
the movie library for a certain track. Currently, this function is only
defined for tracks that are compressed using MPEG.
mvGetTrackMedium returns the type of data stored in the track. Currently
supported media: DM_IMAGE or DM_AUDIO.
mvGetTrackId returns an identifier for the given track that is unique to
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mvGetTrackLength(3dm)mvGetTrackLength(3dm)
that track within the movie and will be saved and restored when the movie
is written and read in from a file. This differs from the track index
which changes as tracks are added or removed.
mvGetTrackMovie returns the MVid of the movie containing the given track.
mvGetTrackDisplayWidth gets the track's display width in the track
spatial coordinate, and mvSetTrackDisplayWidth sets the track's display
width.
mvGetTrackDisplayHeight gets the track's display height in the track
spatial coordinate, and mvSetTrackDisplayHeight sets the track's display
width.
mvGetTrackSMPTEStart returns the starting time code (as set by
mvSetTrackSMPTEStart) stored in the track. The SMPTE time code should be
stored as a string, with two digits each for hour, minute, second, and
frame. For example: "00:59:30:00". The strings returned are owned by
the movie library and must not be freed. If an application needs to keep
the returned string, it should be copied.
mvSetTrackSMPTEStart stores a value in the movie track. It returns
DM_SUCCESS or DM_FAILURE.
SEE ALSOmvIntro(3dm), mvGetImageWidth(3dm), mvGetAudioWidth(3dm),
mvInsertFramesAtTime(3dm), mvEditByFrame(3dm), mvGetErrno(3dm).
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