lorisfrqsplit

lorisfrqsplit — Split partials of a Loris analysis into two sets of partials based on time-varying frequencies.

Syntax

lorisfrqsplit  isrcidx, istoreidx1, istoreidx2, kLowFrq, kHighFrq [, iRollOff, iIncludeHarmonic ]

Description

Frequencies between kLowFrq and kHighFrq is placed in istoreidx1 while the remaining partials are placed in istoreidx2. iRollOff allows the user to specify a crossfade range in Hertz between the boundaries of istoreidx1 and istoreidx2. This is useful for preventing clicks if kLowFrq and kHighFrq are time-varying. iIncludeHarmonic includes integer multiples of frequencies between kLowFrq and kHighFrq in istoreidx1.

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 is a value in Hertz that specifies the size of the crossfade range between partials of istoreidx1 and istoreidx2. See illustration. iRollOff cannot be grater than (kHighFrq-kLowFrq)/2.

if iIncludeHarmonic is 1 then any partials that are integer multiples of kLowFrq to kHighFrq are included in istoreidx1. The default is 0: do not include harmonics.

Performance

kLowFrq is the frequency which forms the lower boundary of istoreidx1.

kHighFrq is the frequency which forms the upper boundary of istoreidx1.

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.