SDIF support in Csound.

For detailed information on  the Sound Description Interchange Format,
refer to the CNMAT website: http://cnmat.CNMAT.Berkeley.EDU/SDIF

If the filename passed to HETRO has the extension .sdif, data will be
written in SDIF format as 1TRC frames of additive synthesis data. The
accompanying utility program "sdif2ads" can be used to convert any
SDIF file containing a stream of 1TRC data to the Csound 'adsyn'
format. 'sdif2ads' allows the user to limit the number of partials
retained, and to apply an amplitude scaling factor. This is often
necessary, as the SDIF specification does not, to date, require
amplitudes to be within a particular range. 'sdif2ads' reports
information about the file to the console, including the frequency
range.

The main advantages of SDIF over the adsyn format, for Csound users,
is that SDIF files are fully portable across platforms (data is
'big-endian'), and do not have the duration limit of 32.76 seconds
imposed by the 16bit adsyn format.This limit is necessarily imposed by
'sdif2ads'. It is planned to incorporate sdif reading directly into
adsyn, thus enabling files of any length (currently memory-permitting)
to be analysed and processed.

It is important to note that the SDIF formats are still under
development, and that while the 1TRC format is now fairly well
established, it can still change.

Some other SDIF resources (including a viewer) are available via the
NC_DREAM website:

http://www.bath.ac.uk/~masjpf/NCD/dreamhome.html

Richard Dobson 5th August 2000
rwd@cableinet.co.uk
