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External SoundObject


Accepts NoteProcessors: no

Allows you to write script within Blue and execute an external program on that script, bringing in generated notes back into Blue. There is a field for 'command line' as well as a text area for your script. When this soundObject is called for generating it's notes, it will write the text within the text area into a temp file and then use the user-supplied 'command line' to execute on that temp file.

When Blue runs the commandline, it defaults to appending the temp file's name to the end of the commandline. For example, if you wrote a perl script in the text area and used a commandline of "perl", then when Blue runs the command, it would be something like "perl /the/path/to/the/tempFile". If you need to explicitly put the name of the temp file somewhere else in the command line than the end, you can use "$infile" in your commandline. For example, if you needed something like "myCommand somefileName -w -d --some-other-flags" and had to have it in that order, you could type "myCommand $infile -w -d --some-other-flags" and Blue will replace that $infile with the temp file's name instead of appending it to the end.

When designing your scripts that you will be using with external programs, you should either set commandline flags to the program or script your script in a way that it will write out to stdout(to the screen), as that is what Blue will capture and bring in as notes.

A second method for the external object was created for bringing in score data after running the commandline as some programs (i.e. Cmask) do not have any possible way to write directly to stdout. The process is to use "$outfile" in the commandline to pass in a filename to the program. That $outfile will be the name of a temp file that the external program will write score data into. After the program is finished, Blue will open up that temp file, read in the score data, and then remove the temp file. So, if your program needed a commandline of something like "myProgram -i inputfilename -o outputfilename" and no options for writing to screen, then you could use a commandline of "myProgram -i $infile -o $outfile".

There is a test button that you may use to check to see that Blue properly brings in the generated notes.

Example Command Lines

This is a list of commandlines to use when using other programs with Blue and any notes that may concern other programs when being used with Blue. These commandlines assume that the programs being called are on the system path. If not on the path, please append the full path to the program before the program name.


Homepage: for the Linux, Windows and old Mac builds, for OSX Author: Andre Bartetzki

Comandline to use:

cmask $infile $outfile

Homepage: Author: Mikel Kuehn

Comandline to use:

ngen $infile $outfile

Homepage: Author: Christopher Ariza

Comandline to use:

python $infile

Examples of the External SoundObject, as well as, can be found in the blue/examples/soundObjects folder.