Audio File In CHOP
The Audio File In CHOP reads audio from files on disk or at
http:// addresses. File types
.wav files are supported. It always outputs time sliced audio data. If you want to record the data, use a Record CHOP or Movie File Out TOP.
For large files the Audio File In CHOP streams the file from disk so loading the entire file into memory is not needed.
- It streams files from disk and from
http:locations (latter copies to local disk first) - It only keeps a few seconds in memory at a time.
- The supported audio files are
.mp3 .aif .aiff .wavand other audio formats.
- It also plays audio-only from any movie files that TouchDesigner supports, like
.mov, .mpg .mp4. See also the Audio Movie CHOP for playing audio from movie files in sync with their video.
- Audio files can be dragged/dropped onto TouchDesigner, double-clicked (if preferred), and RMB Open With... TouchDesigner.
Parameters - Audio File In Page
file - Path of source.
play - Audio will playback when this is set to 1 and stop when set to 0.
playmode - ⊞ - Specifies the method used to playback the audio, there are 3 options.
- Locked to Timeline
locked- This mode locks the playback position to the timeline. Scrubbing or jumping in the timeline will change the song position accordingly. The parameters Play, Reset, Speed, and Index are disabled in this mode since the timeline is directly tied to playback position.
- Specify Index
specify- This mode allows the user to specify a particular position in the song using the Index parameter below. Use this mode for random access to any location in the audio stream.
sequential- This mode continually plays regardless of the timeline position (the Index parameter is disabled). Reset and Speed parameters below are enabled to allow some control.
speed - This is a speed multiplier which only works when Play Mode is Sequential. A value of 1 is the default playback speed. A value of 2 is double speed, 0.5 is half speed and so on. This node can not play audio backwards so negative values will not work well.
cue - Jumps to Cue Point when set to 1. Only available when Play Mode is Sequential.
cuepoint - Set any index in the song as a point to jump to.
Cue Point Unit
index - This parameter explicitly sets the song position when Play Mode is set to Specify Index. The units menu on the right lets you specify the index in the following units: Index, Frames, or Seconds.
repeat - ⊞ - Repeats the audio stream when the end is reached.
trim - Enables the Trim parameters below.
trimstart - Sets an In point from the beginning of the audio, allowing you to trim the starting position of the audio stream. The units menu on the right let you specify this position by index, frames, or seconds.
Trim Start Unit
trimend - Sets an Out point from the end of the audio, allowing you to trim the ending position of the audio stream. The units menu on the right let you specify this position by index, frames, or seconds.
Trim End Unit
prereadlength - The amount of audio to buffer to maintain smooth playback.
Pre-Read Length Unit
opentimeout - The time (in milliseconds) TouchDesigner will wait for the audio file to open. If the Open Timeout time is reached, the Audio File In CHOP will stop waiting, and play silence. If the file still isn't opened the next time the CHOP cooks, it'll wait again, and do the same. It'll keep doing this until the file is opened, or the open fails.
mono - Output mono channel only even if file has multiple channels.
volume - Set the level the file is read in at. A setting of 1 is full signal while 0 is muted.
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).