Difference between revisions of "AudioClip"

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*[[Node Reference]]
 
*[[Node Reference]]
 
==AudioClip==
 
==AudioClip==
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Specification Link: [http://www.web3d.org/documents/specifications/19775-1/V3.3/Part01/components/sound.html#AudioClip AudioClip]
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<pre>
 
<pre>
 
AudioClip : X3DSoundSourceNode, X3DUrlObject {
 
AudioClip : X3DSoundSourceNode, X3DUrlObject {
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   SFBool  [in,out] loop            FALSE
 
   SFBool  [in,out] loop            FALSE
 
   SFNode  [in,out] metadata        NULL  [X3DMetadataObject]
 
   SFNode  [in,out] metadata        NULL  [X3DMetadataObject]
   SFTime  [in,out] pauseTime        0    (-?,?)
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   SFTime  [in,out] pauseTime        0    (-&infin;,&infin;)
   SFFloat  [in,out] pitch            1.0  (0,?)
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   SFFloat  [in,out] pitch            1.0  (0,&infin;)
   SFTime  [in,out] resumeTime      0    (-?,?)
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   SFTime  [in,out] resumeTime      0    (-&infin;,&infin;)
   SFTime  [in,out] startTime        0    (-?,?)
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   SFTime  [in,out] startTime        0    (-&infin;,&infin;)
   SFTime  [in,out] stopTime        0    (-?,?)
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   SFTime  [in,out] stopTime        0    (-&infin;,&infin;)
   MFString [in,out] url              []    [urn]
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   MFString [in,out] url              []    [URI]
 
   SFTime  [out]    duration_changed
 
   SFTime  [out]    duration_changed
 
   SFTime  [out]    elapsedTime
 
   SFTime  [out]    elapsedTime
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</pre>
 
</pre>
  
<p>An AudioClip node specifies audio data that can be referenced by Sound nodes.</p>
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==DTD Validation==
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===Children===
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Children must appear as follows:
  
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# A single, optional IS.
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# A single, optional node derived from ''X3DMetadataObject'' for the ''metadata'' field.
  
<p>The description field specifies a textual description of the audio source. A browser is not required to display the description field but may choose to do so in addition to playing the sound.</p>
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===Attributes===
  
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* There are no limits on the acceptable range of values for the ''pitch'' field.
  
<p>The url field specifies the URL from which the sound is loaded. Browsers shall support at least the wavefile format in uncompressed PCM format (see [WAV]). It is recommended that browsers also support the MIDI file type 1 sound format (see 2.[MIDI]) and the MP3 compressed format (see 2.[I11172-1]). MIDI files are presumed to use the General MIDI patch set. 9.2.1 URLs contains details on the url field.</p>
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==Schema Validation==
  
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===Children===
  
<p>The loop, pauseTime, resumeTime, startTime, and stopTime inputOutput fields and the elapsedTime, isActive, and isPaused outputOnly fields, and their effects on the AudioClip node, are discussed in detail in 8 Time component. The "cycle" of an AudioClip is the length of time in seconds for one playing of the audio at the specified pitch.</p>
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Children must appear as follows:
  
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# A single, optional IS.
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# A single, optional node derived from ''X3DMetadataObject'' for the ''metadata'' field.
  
<p>The pitch field specifies a multiplier for the rate at which sampled sound is played. Values for the pitch field shall be greater than zero. Changing the pitch field affects both the pitch and playback speed of a sound. A set_pitch event to an active AudioClip is ignored and no pitch_changed field is generated. If pitch is set to 2.0, the sound shall be played one octave higher than normal and played twice as fast. For a sampled sound, the pitch field alters the sampling rate at which the sound is played. The proper implementation of pitch control for MIDI (or other note sequence sound clips) is to multiply the tempo of the playback by the pitch value and adjust the MIDI Coarse Tune and Fine Tune controls to achieve the proper pitch change.</p>
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===Attributes===
  
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* There ''pitch'' field is restricted to positive values, i.e. greater than zero.
  
<p>A duration_changed event is sent whenever there is a new value for the "normal" duration of the clip. Typically, this will only occur when the current url in use changes and the sound data has been loaded, indicating that the clip is playing a different sound source. The duration is the length of time in seconds for one cycle of the audio for a pitch set to 1.0. Changing the pitch field will not trigger a duration_changed event. A duration value of "-1" implies that the sound data has not yet loaded or the value is unavailable for some reason. A duration_changed event shall be generated if the AudioClip node is loaded when the X3D file is read or the AudioClip node is added to the scene graph.</p>
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==Schematron validation==
<p>The isActive field may be used by other nodes to determine if the clip is currently active. If an AudioClip is active, it shall be playing the sound corresponding to the sound time (i.e., in the sound's local time system with sample 0 at time 0):</p>
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TBD
  
<pre>t = (now - startTime) modulo (duration / pitch)</pre>
 
 
*[[Node Reference]]
 
*[[Node Reference]]

Latest revision as of 09:39, 24 April 2015

AudioClip

Specification Link: AudioClip

AudioClip : X3DSoundSourceNode, X3DUrlObject {
  SFString [in,out] description      ""
  SFBool   [in,out] loop             FALSE
  SFNode   [in,out] metadata         NULL  [X3DMetadataObject]
  SFTime   [in,out] pauseTime        0     (-∞,∞)
  SFFloat  [in,out] pitch            1.0   (0,∞)
  SFTime   [in,out] resumeTime       0     (-∞,∞)
  SFTime   [in,out] startTime        0     (-∞,∞)
  SFTime   [in,out] stopTime         0     (-∞,∞)
  MFString [in,out] url              []    [URI]
  SFTime   [out]    duration_changed
  SFTime   [out]    elapsedTime
  SFBool   [out]    isActive
  SFBool   [out]    isPaused
}

DTD Validation

Children

Children must appear as follows:

  1. A single, optional IS.
  2. A single, optional node derived from X3DMetadataObject for the metadata field.

Attributes

  • There are no limits on the acceptable range of values for the pitch field.

Schema Validation

Children

Children must appear as follows:

  1. A single, optional IS.
  2. A single, optional node derived from X3DMetadataObject for the metadata field.

Attributes

  • There pitch field is restricted to positive values, i.e. greater than zero.

Schematron validation

TBD