an open-source digital signal processing and sound synthesis language
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STEREO -- mix input to stereo output with adjustable pan
in RTcmix/insts/std

quick syntax:
STEREO(outsk, insk, dur, AMP, P4-N: input/output channel pan assigns)

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.

   p0 = output start time (seconds)
   p1 = input start time (seconds)
   p2 = duration (or endtime if negative) (seconds)
   p3 = amplitude multiplier (relative multiplier of input signal)
   p4-n = input/output channel pan assigns (0-1 stereo; 0.5 is middle)

   p3 (amplitude) and the p4-n (pan assigns) pfields can receive dynamic
   updates from a table or real-time control source.

   Author:  Brad Garton; rev. for v4.0 by JGG, 7/9/04

STEREO will mix any number of input channels to stereo outputs with global amplitude control and individual pans for each input channel.

Usage Notes

STEREO mixes channels from the input source into the stereo output, according to the 'input/output channel pan assign' in the p4-n pfields. The total number ("n") of these pfields will depend on how many channels are present in the input. These pfields together constitute a 'mix matrix', in which argument position represents input channel number, and argument value represents output stereo location. These output locations are expressed as a 0-1 value, with 0.5 being in the middle (0 == left channel, 1 == right channel.

It works like this: For every input channel, the corresponding number in the pfield (starting with p4) gives the output stereo pan for that channel (0-1, 0.5 in middle). Thus p4 corresponds to input channel 0, p5 corresponds to input channel 1, etc. If the value of one of these pfields is negative, then the corresponding input channel will not be played. Note that you cannot send a channel to more than one output pan location.

Each of these individual input pan values can received dynamic updates through the pfield-enabled control system.

STEREO requires stereo output (obviously).

Sample Scores

very basic:
   rtsetparams(44100, 2)


   loc = 0.75
   STEREO(outskip=0, inskip=1, dur=3, amp=1, loc)

slightly more advanced:
   rtsetparams(44100, 2)


   ampenv = maketable("line", 1000, 0,0, 1,1, 1.1, 0)
   STEREO(0, 0, 3.5, 0.7*ampenv, 0.5, 0.5)

   ampenv = maketable("line", 1000, 0,0, 0.1,1, 1, 0)
   STEREO(2, 0, 3.5, 0.6*ampenv, 0.1, 0.1)

fun stuff!
   rtsetparams(44100, 2)


   ampenv = maketable("line", 1000, 0,0, .1,1, 2,0)

   dur = 1
   for(outsk = 0; outsk < 10.0; outsk = outsk + dur) {
      insk = random() * 7.0
      dur = random() * 0.2
      STEREO(insk, outsk, dur, 1, random(), -1)

See Also