Writing to Disk

by Adam Tindale and Ge Wang

Recording your ChucK session to file is easy!

Say you want to record the output of the following:


All you have to do is ChucK a shred that writes to file:


No changes to existing files are necessary. An example can be found in examples/basic/, this guy/gal writes to “foo.wav”. Edit the file to change the output file. If you don’t want to worry about overwriting the same file everytime, you can substitute for

%>chuck will generate a file name using the current time. You can change the prefix of the filename by modifying

"data/session" => w.autoPrefix;

w is the WvOut in the patch.

Oh yeah, you can of course chuck on-the-fly.

From terminal 1

%>chuck --loop

From terminal 2

%>⁞chuck +

Silent Mode

You can write directly to disk without having real-time audio by starting your programs using the --silent or -s flag.
%>chuck -s

This will not synchronize to the audio card, and will generate samples as fast as it can.

Start and Stop

You can start and stop the writing to file by:
1 => w.record; // start
0 => w.record; // stop

As with all things ChucKian, this can be done sample-synchronously.

Another halting problem

What if I have infinite time loop, and want to terminate the VM, will my file be written out correctly? the answer: Ctrl-C works just fine.

ChucK STK module keeps track of open file handles and closes them even upon abnormal termination, like Ctrl-C. Actually for many, Ctrl-C is the natural way to end your ChucK session. At any rate, this is quite ghetto, but it works. As for seg-faults and other catastrophic events, like computer catching on fire from ChucK exploding, the file probably is toast.

hmmmm, toast...

The Silent Sample Sucker Strikes Again

As in, one patch to write to file is:
dac => Gain g => WvOut w => blackhole;

The WvOut writes to file, and also pass through the incoming samples.