Audio Play CHOP
The Audio Play CHOP plays back a sound file through any attached audio output device using DirectSound. It supports
.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.
The file can be read in from disk or from the web. Use
http:// when specifying a URL.
Parameters - AudioPlay Page
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.
.m4a audio file. The file can be mono or stereo.
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 - 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 - ⊞ - Determines how the audio is triggered when using the first input to trigger.
- Play While On
on- Plays while input is 1.
trigger- Triggers once when input goes to 1.
loop- Plays and loops when input goes to 1.
trigger - Triggers the audio to play.
Cook Every Frame
cookalways - Forces CHOP to cook every frame.
Parameters - Output 1 Page
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 of Center
Front Right of Center
Parameters - Output 2 Page
The following speaker outputs are found on this parameter page.
Top Front Left
Top Front Center
Top Front Right
Top Back Left
Top Back Center
Top Back Right
Parameters - Common Page
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 - 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.
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
autoexportroot - This path points to the root node where all of the paths that exporting by Channel Name is Path:Parameter are relative to.
exporttable - The DAT used to hold the export information when using the DAT Table Export Methods (See above).
- Input 0 -
- Input 1 -
- Input 2 -
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A custom interactive control panel built within TouchDesigner. Panels are created using Panel Components whose look is created entirely with TOPs.
To re-compute the output data of the Operators. An operator cooks when (1) its inputs change, (2) its Parameters change, (3) when the timeline moves forward in some cases, or (4) Scripting commands are run on the node. When the operator is a Gadget, it also cooks when a user interacts with it. When an operator cooks, it usually causes operators connected to its output to re-cook. When TouchDesigner draws the screen, it re-cooks all the necessary operators in all Networks, contributing to a frame's total "cook time".
The term "Frame" is used (1) in the Timeline, (2) as a time-unit in CHOPs, (3) as a time-unit in TOPs, and (4) with movies images which are read and created with TOPs.
A Time Slice is the time from the last cook frame to the current cook frame. In CHOPs it is the set of short channels that only contain the CHOP channels' samples between the last and the current cook frame.
A parameter in most CHOPs that restricts which channels of that CHOP will be affected. Normally all channels of a CHOP are affected by the operator.
samples-per-second of a CHOP. Each CHOP in your network has a sample rate, whether it is used or not. The overall timeline has a "frame rate", which is the number of animation frames per second, generally your monitor display frequency.
Exporting is the connection of CHOP channels to parameters of operators. The output of each exporting CHOP is one or more channels, active only while the CHOP Viewer is on. The current value of a channel can be exported to a parameter of any operator, overriding that parameter's value. See Parameter.
Parameters in TouchDesigner are an operator's settings (numbers, menus, flags, strings, paths) which the user can alter. Parameters for any operator can be opened by right-clicking on the operator and selecting "Parameters..." A currently selected operator's parameters can be viewed in a Network Editor by pressing the keyboard shortcut 'p'.