Maven module :un.storage : media-mpeg4 :
Class : un.storage.media.mp4.boxes.impl.TrackHeaderBox
Extends/Implements : un.storage.media.mp4.boxes.FullBox
Subclasses : -

This box specifies the characteristics of a single track. Exactly one Track
Header Box is contained in a track. In the absence of an edit list, the
presentation of a track starts at the beginning of the overall presentation.
An empty edit is used to offset the start time of a track.
If in a presentation all tracks have neither trackInMovie nor trackInPreview
set, then all tracks shall be treated as if both flags were set on all
tracks. Hint tracks should not have the track header flags set, so that they
are ignored for local playback and preview.
The width and height in the track header are measured on a notional 'square'
(uniform) grid. Track video data is normalized to these dimensions
(logically) before any transformation or placement caused by a layup or
composition system. Track (and movie) matrices, if used, also operate in this
uniformly-scaled space.

@author Alexander Simm

Variables : -
Functions : TrackHeaderBox, decode, isTrackEnabled, isTrackInMovie, isTrackInPreview, getCreationTime, getModificationTime, getTrackID, getDuration, getLayer, getAlternateGroup, getVolume, getWidth, getHeight, getMatrix

public void TrackHeaderBox ()

public void decode (MP4InputStream in)


A flag indicating that the track is enabled. A disabled track is treated
as if it were not present.
return  true if the track is enabled
public boolean isTrackEnabled ()


A flag indicating that the track is used in the presentation.
return  true if the track is used
public boolean isTrackInMovie ()


A flag indicating that the track is used when previewing the
presentation.
return  true if the track is used in previews
public boolean isTrackInPreview ()


The creation time is an integer that declares the creation time of the
presentation in seconds since midnight, Jan. 1, 1904, in UTC time.
return  the creation time
public long getCreationTime ()


The modification time is an integer that declares the most recent time
the presentation was modified in seconds since midnight, Jan. 1, 1904,
in UTC time.
public long getModificationTime ()


The track ID is an integer that uniquely identifies this track over the
entire life-time of this presentation. Track IDs are never re-used and
cannot be zero.
return  the track's ID
public int getTrackID ()


The duration is an integer that indicates the duration of this track (in
the timescale indicated in the Movie Header Box). The value of this field
is equal to the sum of the durations of all of the track's edits. If
there is no edit list, then the duration is the sum of the sample
durations, converted into the timescale in the Movie Header Box. If the
duration of this track cannot be determined then this value is -1.
return  the duration this track
public long getDuration ()


The layer specifies the front-to-back ordering of video tracks; tracks
with lower numbers are closer to the viewer. 0 is the normal value, and
-1 would be in front of track 0, and so on.
@return the layer
public int getLayer ()


The alternate group is an integer that specifies a group or collection
of tracks. If this field is 0 there is no information on possible
relations to other tracks. If this field is not 0, it should be the same
for tracks that contain alternate data for one another and different for
tracks belonging to different such groups. Only one track within an
alternate group should be played or streamed at any one time, and must be
distinguishable from other tracks in the group via attributes such as
bitrate, codec, language, packet size etc. A group may have only one
member.
return  the alternate group
public int getAlternateGroup ()


The volume is a floating point number that indicates the preferred
playback volume: 0.0 is mute, 1.0 is normal volume.
return  the volume
public double getVolume ()


The width specifies the track's visual presentation width as a floating
point values. This needs not be the same as the pixel width of the
images, which is documented in the sample description(s); all images in
the sequence are scaled to this width, before any overall transformation
of the track represented by the matrix. The pixel dimensions of the
images are the default values.
return  the image width
public double getWidth ()


The height specifies the track's visual presentation height as a floating
point value. This needs not be the same as the pixel height of the
images, which is documented in the sample description(s); all images in
the sequence are scaled to this height, before any overall transformation
of the track represented by the matrix. The pixel dimensions of the
images are the default values.
return  the image height
public double getHeight ()

public double[] getMatrix ()