Pitch-transposiion using 3rd-order interpolation.

in RTcmix/insts/std

quick syntax:

TRANS3(outsk, insk, dur, AMP, TRANSP[, inputchan, PAN])

CAPITALIZED parameters are pfield-enabled for table or dynamic control (see the maketable or makeconnection scorefile commands). Parameters after the [bracket] are optional and default to 0 unless otherwise noted.

Param Field Parameter Units Dynamic Optional Notes
p0 output start time seconds no no  
p1 input start time seconds no no  
p2 output duration (or endtime if negative) seconds no no  
p3 amplitude multiplier relative multiplier of input signal yes no  
p4 interval of transposition oct.pc yes no  
p5 input channel - no yes default: 0
p6 pan 0-1 stereo; 0.5 is middle yes yes default: 0

Parameters labled as Dynamic can receive dynamic updates from a table or real-time control source.

Author: Doug Scott; rev. for v4 by JG, 2/11/06

TRANS3 transposes the input for the specified output duration (p2), starting at the input start time (p1). It has the same syntax as TRANS and is used in the same fashion. The difference is that TRANS3 uses 3rd-order interpolation to achieve the pitch-shift. This is s a bit more expensive computationally, but it does produce smoother results.

Usage Notes

The use of TRANS3 is identical to the TRANS instrument. See the TRANS Usage Notes for more information.

Sample Scores

very basic:

   rtsetparams(44100, 2)
   load("TRANS") // note that TRANS3 is loaded in the TRANS library


   trans = -0.02
   // do both channels of a stereo input file
   TRANS3(outskip=1, inskip=2, dur=4, amp=1, trans, inchan=0, pan=0)
   TRANS3(outskip=1, inskip=2, dur=4, amp=1, trans, inchan=1, pan=1)

slightly more advanced:

   rtsetparams(44100, 2)


   start = 0
   inskip = 0
   dur = 7.8
   amp = 1.0
   ampenv = maketable("line", 1000, 0,0, 1,1, 7,1, 7.8,0)

   low = octpch(-0.05)
   high = octpch(0.03)
   transp = maketable("line", "nonorm", 1000, 0,0, 1,low, 3,high)
   transp = makeconverter(transp, "pchoct")

   This transposition starts at 0, moves down by a perfect fourth (-0.05),
   then up to a minor third (0.03) above the starting transposition.  The
   table is expressed in linear octaves, then converted to octave.pc by the
   call to makeconverter.
   TRANS3(start, inskip, dur, amp*ampenv, transp)

See Also

maketable, makeconverter, MOCKBEND, SCRUB, TRANS, TRANSBEND, PVOC