lorisnoisesplit

lorisnoisesplit — Split partials of a Loris analysis into two sets of partials based on time-varying noise coefficients.

Syntax

lorisnoisesplit  isrcidx, istoreidx1, istoreidx2, kLowNoise, kHighNoise [, iRollOff ]

Description

Partials with noise coefficients between kLowNoise and kHighNoise are placed in istoreidx1 while the remaining partials are placed in istoreidx2. iRollOff allows the user to specify a crossfade range between the boundaries of istoreidx1 and istoreidx2. This is useful for preventing clicks if kLowNoise and kHighNoise are time-varying.

Initialization

isrcidx is an integer label that identifies the stored set of SDIF partials that are used. Use lorisread to import partials from an SDIF file, store them in memory and assign a label.

istoreidx1, istoreidx2 are integer labels where the partial data resulting from this opcode will be stored. These labels may be subsequently used with any other loris opcode for further transformation or resynthesis with lorisplay. if istoreidx1/istoreidx2 and isrcidx are identical then the original set of partial data is overwritten.

iRollOff specifies the size of the raw-amplitude crossfade between partials of istoreidx1 and istoreidx2. See illustration. iRollOff cannot be greater than (kHighNoise-kLowNoise)/2.

Performance

kLowNoise is the noise coefficient which forms the lower boundary of istoreidx1.

kHighNoise is the noise coefficient which forms the upper boundary of istoreidx1.

Warning! Only an SDIF file that uses the RBEP frame type will contain bandwidth-enhanced partials (noise coefficients). If you are using another frame type (such as Audiosculpt's or SPEAR's 1TRC), resynthesis will work properly but all noise coefficients will be 0. You can alter them, but only at your own peril!

Credits

The Loris unit generators were written by Kelly Fitz (loris@cerlsoundgroup.org). It is patterned after a prototype implementation of the lorisplay unit generator written by Corbin Champion, and based on the method of Bandwidth-Enhanced Additive Synthesis and on the sound morphing algorithms implemented in the Loris library for sound modeling and manipulation. The opcodes were further adapted as a plugin for Csound 5 by Michael Gogins. Ben Hackbarth (hackbarth@ucsd.edu) wrote the Extended Loris Opcodes.