Audio Play CHOP


The Audio Play CHOP plays back a sound file through any attached audio output device using DirectSound. It supports .aif, .mp3, .mid, .wav and .m4a files up to 48.000 kHz, which can have mono, stereo or even up to 5.1 channels in them. The audio channels can then be routed to any speaker location that DirectSound uses. See Outputs section below.

NOTE: With the Audio Play CHOP, audio samples do not enter or pass through TouchDesigner, so you will not see them in CHOPs, and you cannot process them in CHOPs. The Audio Play CHOP starts an external process that opens the file and sends it directly to the the audio outputs of your computer. If you want to process the audio within TouchDesigner or output them into a Movie File Out TOP or Audio Device Out CHOP, use the Audio File In CHOP.

The Audio Play CHOP contains a channel called state. This channel is 1 whenever any file is being played, 0 otherwise.

The first input (Input 0:Triggers) is used to trigger the audio file to play. The second input (Input 1: Volume) can be used to control volume, if no input is connected the Volume parameter will be used. The third input (Input 2: Pan) is for panning, no input assumes it is centered. When using the DAT List parameter, the inputs can contain mulitiple channels to manipulate each file individually. Multiple Audio Play CHOPs can output to different devices simutaneously.

It can also be triggered by the Trigger parameter below, but in this case if multiple files are specified via the DAT List, then all files will be played at the same time when triggered.

Sound files can also be triggered through the play() method audioplayCHOP_Class. Some advanced options are only available through the audioplayCHOP_Class.

The file can be read in from disk or from the web. Use http:// when specifying a URL.


Parameters - AudioPlay Page

Device device - A menu of available audio devices to output to. Selecting default sets the audio device to that which is selected in Windows Control Panel>Sound>Playback.  

Outputs outputs -  

Sound File file - .aif, .mp3, .mid, .wav or .m4a audio file. The file can be mono or stereo.  

DAT List datlist - Links to a Table DAT which can be used as list of audio files to choose from. When using the DAT List, the first input (Input 0: Triggers) on the CHOP can contain mulitiple channels to fire the files in the list individually. Using the audioplay command the index can be specified directly.  

Volume volume - 0 = mute, 1 = full volume. Using the second input (Input 1: Volume) or the python .play(volume=val) method, will override the value of this parameter.  

Mode mode - - Determines how the audio is triggered when using the first input to trigger.

  • Play While On on - Plays while input is 1.
  • Trigger trigger - Triggers once when input goes to 1.
  • Loop loop - Plays and loops when input goes to 1.

Trigger trigger - Triggers the audio to play.  

Cook Every Frame cookalways - Forces CHOP to cook every frame.  

Parameters - Output 1 Page

Stereo Mode stereo - Sets output to just 2 channels, front left and front right.

Outputs - The outputs on this page and the following Output 2 page are for routing to an audio device's different speaker outputs. Not all devices will support all outputs. For each speaker output, you can route any of the file's channels to play through it. For example, you can easily output the front left channel of the file to the all the front left speaker outputs, or you could output the front left channel to both front and rear speaker outputs. The value of each output parameter determines which channel from the file it plays, see below.

  • -1 - no audio plays through this output
  • 0 - front left channel will play
  • 1 - front right channel will play
  • 2 - rear left channel will play
  • 3 - rear right channel will play
  • 4 - center channel will play
  • 5 - sub or low frequency channel will play

The following speaker outputs are found on this parameter page.  

Front Left frontleft -  

Front Right frontright -  

Front Center frontcenter -  

Low Frequency lowfrequency -  

Back Left backleft -  

Back Right backright -  

Front Left of Center frontleftcenter -  

Front Right of Center frontrightcenter -  

Back Center backcenter -  

Parameters - Output 2 Page

The following speaker outputs are found on this parameter page.

Side Left sideleft -  

Side Right sideright -  

Top Center topcenter -  

Top Front Left topfrontleft -  

Top Front Center topfrontcenter -  

Top Front Right topfrontright -  

Top Back Left topbackleft -  

Top Back Center topbackcenter -  

Top Back Right topbackright -  

Parameters - Common Page

Time Slice timeslice - Turning this on forces the channels to be "Time Sliced". A Time Slice is the time between the last cook frame and the current cook frame.  

Scope scope - To determine which channels get affected, some CHOPs use a Scope string on the Common page.  

Sample Rate Match srselect - - Handle cases where multiple input CHOPs' sample rates are different. When Resampling occurs, the curves are interpolated according to the Interpolation Method Option, or "Linear" if the Interpolate Options are not available.

  • Resample At First Input's Rate first - Use rate of first input to resample others.
  • Resample At Maximum Rate max - Resample to the highest sample rate.
  • Resample At Minimum Rate min - Resample to the lowest sample rate.
  • Error If Rates Differ err - Doesn't accept conflicting sample rates.

Export Method exportmethod - - This will determine how to connect the CHOP channel to the parameter. Refer to the Export article for more information.

  • DAT Table by Index datindex - Uses the docked DAT table and references the channel via the index of the channel in the CHOP.
  • DAT Table by Name datname - Uses the docked DAT table and references the channel via the name of the channel in the CHOP.
  • Channel Name is Path:Parameter autoname - The channel is the full destination of where to export to, such has geo1/transform1:tx.

Export Root autoexportroot - This path points to the root node where all of the paths that exporting by Channel Name is Path:Parameter are relative to.  

Export Table exporttable - The DAT used to hold the export information when using the DAT Table Export Methods (See above).  

Operator Inputs

  • Input 0 -
  • Input 1 -
  • Input 2 -

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