lorispartial

lorispartial — Manipulate the frequency, amplitude and noisiness of a single partial of a Loris analysis.

Syntax

lorispartial isrcidx, istoreidx, kparnumber, kfrq, kamp, knoise [, imethod, isolo ]

Description

Allows the user to access the kparnumber partial of isrcidx, modify it and place it in istoreidx.

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.

itgtidx is an integer label where the partial data created by this opcode will be stored. This label may be subsequently used with any other loris opcode for further transformation or resynthesis with lorisplay. if itgtidx and isrcidx are identical then isrcidx is overwritten.

if imethod is 0 then kfrq, kamp and knoise scale (multiply) the resynthesis parameters. If imethod is 1 then kfrq, kamp and knoise are added to the resynthesis parameters. The default is 0.

If isolo is 0 then all other unmodified partials are included in isrcidx. If isolo is 1 then only partial kparnumber is included. The default is 0.

Performance

kparnumber is the integer label of the partial to modify. Partial labels are automatically assigned by Loris during analysis. With the lorispartial opcode, the first partial number of any imported analysis is 1.

kfrq is a control-rate transposition factor: a value of 1 incurs no transposition, 1.5 transposes up a perfect fifth, and .5 down an octave.

kamp is a control-rate scale factor that is applied to all partial amplitude envelopes.

knoise is a control-rate scale factor that is applied to all partial bandwidth or noisiness envelopes.

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.