NAME

rtoutput - open a new sound file for writing

SYNOPSIS

rtoutput(file_name [, header_type ] [, data_format ])

DESCRIPTION

Call rtoutput to open a new sound file for subsequent writing by real-time instruments.

After rtoutput creates a sound file, it prints information about the file, such as the header type and sampling rate.

The older disk-based Cmix instruments use output to open files for writing, not rtoutput.

ARGUMENTS

file_name

The name of a sound file, in double-quotes. If the file already exists, the script will terminate with an error, unless you've turned on file clobbering with set_option (by saying set_option(``clobber_on'')).

header_type

The type of header to use for the sound file, as a double-quoted string.

aiff: AIFF format
aifc: AIFC format (uncompressed)
wav: Microsoft RIFF (Wav) format
next: NeXT format (same as sun)
sun: Sun ``au'' format (same as next)
ircam: IRCAM format (the older, non-hybrid BICSF format)
raw: raw (headerless) format

AIFF is the default if no header type is given.

data_format

The type of data format to use for the sound file, as a double-quoted string.

NOTE: The sampling rate and number of channels are specified in a call to rtsetparams at the beginning of the script.

short: 16-bit linear
float: 32-bit floating point
normfloat: 32-bit floating point, with samples normally between -1 and +1.
16: synonym for ``short''

``short'' is the default if no data format is given.

NOTES

If you don't want RTcmix to play while you're writing a file, use set_option to turn off playing before you invoke any instruments, by saying set_option(``audio_off'').

The case of the header_type and data_format arguments is not significant, nor is their order.

All formats are big-endian, except for ``wav,'' which is always little-endian, and ``raw,'' which has host byte order.

If you ask for ``aiff'' and ``float'' (or ``normfloat''), you'll get ``aifc'' format instead, because AIFF doesn't support floating-point files.

If you want to use floating-point files in the Snd, choose ``normfloat'' format. If you want to use them in Mxv, choose the ``next'' header type. Many programs don't read AIFC files, maybe because they assume these are always compressed.

EXAMPLES

   rtsetparams(22050, 2)
   rtoutput("mysound")

writes a stereo, 16-bit linear AIFF file with 22050 sampling rate.

   rtsetparams(44100, 1)
   set_option("audio_off", "clobber_on")
   rtoutput("myothersound", "wav", "float")