It also requires that function table 1 be filled with a sine wave, which is accomplished by the following card:
makegen(1,1024,10,1)
The first two arguments for lpc specify time to start writing on the output file (opened previously with an output card, and the duration of the resynthesis.
The third argument determines the manor and value of pitch transposition (if any) to be used. If the absolute value of this argument is smaller than one, it is interpretted as an octave point pitch class absolute transposition. For example ".07" would result in an upward transposition of a fifth (7 semitones) while "-.175" would result in a downward transpostion of an octave plus a fourth plus a quarter tone. Note that a more detailed transposition curve can be outlined using optional couplets from p[7],p[8] ... p[n-1],p[n]. In this case, the first member of each couplet is a frame number -- the second is the transposition to be used at that frame number. Linear interpolation is made between all the couplets specified. Frames not covered by these pairs of couplets default to the transposition in p[2].
The next two arguments (p[3],p[4]) are the first and last frames from the analysis to be used in the resynthesis.
p[5] is the relative amplitude of the resynthesis.
p[6] is the "warp" factor to be used. Warping is an attempt to simulate the non-linear formant shifting that occurs in the transposition of carbon-based vibrating bodies. It is a fudge, but a pretty good one. Values should range from 0 (no warping) to 10 (tons of compensation for the given transposition).