QTTrack Class Reference

Inherits from
Conforms to
Framework
/System/Library/Frameworks/QTKit.framework
Availability
Available in OS X v10.4 and later.
Declared in
QTTrack.h

Overview

A QTTrack object is an object that represents the ordering and other characteristics of media data in a QTMovie object, such as a single video track or audio track. A QTMovie object typically contains one or more streams of media data, which are represented by QTTrack objects. When a QTMovie object has been initialized with QTMovieOpenForPlaybackAttribute set to NO, a QTTrack object wraps the underlying QuickTime track (of type Track). A QTMovie object may have several QTTrack objects associated with it. By constrast, a QTTrack object has exactly one QTMedia object associated with it.

Tasks

Creating a QTTrack

Initializing a QTTrack

Getting Track Properties

Setting Track Properties

Editing Track Properties

Getting QTTrack Primitives

Getting and Setting Aperture Mode Dimensions

Constants

Track Attributes

The following constants specify the track attributes that you can get and set using the trackAttributes and setTrackAttributes methods. To get or set a single attribute, use attributeForKey or setAttribute.

NSString * const QTTrackBoundsAttribute;
NSString * const QTTrackCreationTimeAttribute;
NSString * const QTTrackDimensionsAttribute;
NSString * const QTTrackDisplayNameAttribute;
NSString * const QTTrackEnabledAttribute;
NSString * const QTTrackFormatSummaryAttribute;
NSString * const QTTrackIsChapterTrackAttribute;
NSString * const QTTrackHasApertureModeDimensionsAttribute;
NSString * const QTTrackIDAttribute;
NSString * const QTTrackLayerAttribute;
NSString * const QTTrackMediaTypeAttribute;
NSString * const QTTrackModificationTimeAttribute;
NSString * const QTTrackRangeAttribute;
NSString * const QTTrackTimeScaleAttribute;
NSString * const QTTrackUsageInMovieAttribute;
NSString * const QTTrackUsageInPosterAttribute;
NSString * const QTTrackUsageInPreviewAttribute;
NSString * const QTTrackVolumeAttribute;
Constants
QTTrackBoundsAttribute

The bounding rectangle of a QTTrack object; the value for this key is of type NSValue, interpreted as an NSRect.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackCreationTimeAttribute

The creation time of a QTTrack object; the value for this key is of type NSDate.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackDimensionsAttribute

The dimensions of a QTTrack object; the value for this key is of type NSValue, interpreted as an NSSize.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackDisplayNameAttribute

The display name of a QTTrack object; the value for this key is of type NSString.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackEnabledAttribute

The track enabled state of a QTTrack object; the value for this key is of type NSNumber, interpreted as a BOOL.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackFormatSummaryAttribute

An NSString that is a localized, human-readable string that summarizes a track’s format; for example, “16-bit Integer (Big Endian), Stereo (L R), 48.000 kHz”.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Declared in QTTrack.h.

OS X v10.5 and later.

Deprecated in OS X v10.9.

QTTrackIsChapterTrackAttribute

Whether a QTTrack object is a chapter track for some other QTTrack object; the value for this key is of type NSNumber, interpreted as a BOOL.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.5 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackHasApertureModeDimensionsAttribute

Whether aperture mode dimensions have been set on a QTTrack object; the value for this key is of type NSNumber, interpreted as a BOOL.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.5 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackIDAttribute

The track ID of a QTTrack object; the value for this key is of type NSNumber, interpreted as a long.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackLayerAttribute

The track layer of a QTTrack object; the value for this key is of type NSNumber, interpreted as a short.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackMediaTypeAttribute

The media type of a QTTrack object; the value for this key is of type NSString.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackModificationTimeAttribute

The modification time of a QTTrack object; the value for this key is of type NSDate.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackRangeAttribute

The range of time this track occupies; the value for this key is of type NSValue, interpreted as a QTTimeRange.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackTimeScaleAttribute

The time scale of a QTTrack object; the value for this key is of type NSNumber, interpreted as a long.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackUsageInMovieAttribute

Whether a QTTrack object contributes data to the movie; the value for this key is of type NSNumber, interpreted as a BOOL.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackUsageInPosterAttribute

Whether a QTTrack object contributes data to the movie poster; the value for this key is of type NSNumber, interpreted as a BOOL.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackUsageInPreviewAttribute

Whether a QTTrack object contributes data to the movie preview; the value for this key is of type NSNumber, interpreted as a BOOL.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.

QTTrackVolumeAttribute

The volume of a QTTrack object; the value for this key is of type NSNumber, interpreted as a float.

This attribute can be read and written. This attribute can be read and written when the movie containing this track has been initialized with QTMovieOpenForPlaybackAttribute set to YES.

Available in OS X v10.4 and later.

Deprecated in OS X v10.9.

Declared in QTTrack.h.