readk4 — Periodically reads four orchestra control-signal values from an external file.
ifilname -- an integer N denoting a file named "readk.N" or a character string (in double quotes, spaces permitted) denoting the external file name. For a string, it may either be a full path name with directory specified or a simple filename. In the later case, the file is sought first in the current directory, then in SSDIR, and finally in SFDIR.
iformat -- specifies the input data format:
1 = 8-bit signed integers (char)
4 = 16-bit short integers
5 = 32-bit long integers
6 = 32-bit floats
7 = ASCII long integers (plain text)
8 = ASCII floats (plain text)
Note that A-law and U-law formats are not available, and that all formats except the last two are binary. The input file should be a "raw", headerless data file.
iprd -- the rate (period) in seconds, rounded to the nearest orchestra control period, at which the signals are read from the input file. A value of 0 implies one control period (the enforced minimum), which will read new values at the orchestra control rate. Longer periods will cause the same values to repeat for more than one control period.
kr1, kr2, kr3, kr4 -- output of the signals read from ifilname.
This opcode allows four generated control signal values to be read from a named external file. The file should contain no header information but it should contain a regularly sampled time series of control values. For binary formats, the individual samples of each signal are interleaved. For ASCII text formats, the values are assumed to be separated by at least one whitespace character. The four "channels" in a sample frame may be on the same line or separated by newline characters, it does not matter. There may be any number of readk4 opcodes in an instrument or orchestra and they may read from the same or different files.
Here is an example of the readk4 opcode. It uses the file readk4.csd.
Example 879. Example of the readk4 opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform -odac ;;;realtime audio out ;-iadc ;;;uncomment -iadc if realtime audio input is needed too ; For Non-realtime ouput leave only the line below: ; -o readk4.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 giSine ftgen 0, 0, 2^10, 10, 1 instr 1 ;writes four control signals to a file kcf randh 950, 1, 2, 1, 1050 ;generates one random number between 100 and 2000 per second kq randh 10, 1, 2, 1, 11 ;generates another random number between 1 and 21 per second kdb randh 9, 1, 2, 1, -15 ;amplitudes in dB between -24 and -6 kpan randh .5, 1, 2, 1, .5 ;panning between 0 and 1 dumpk4 kcf, kq, kdb, kpan, "dumpk4.txt", 8, 1 ;writes the control signals prints "WRITING:\n" printks "kcf = %f, kq = %f, kdb = %f, kpan = %f\n", 1, kcf, kq, kdb, kpan ;prints them endin instr 2 ;reads the file written by instr 1 kcf,kq,kdb,kp readk4 "dumpk4.txt", 8, 1 prints "READING:\n" printks "kcf = %f, kq = %f, kdb = %f, kpan = %f\n", 1, kcf, kq, kdb, kp ;prints values kdb lineto kdb, .1 ;smoothing amp transition kp lineto kp, .1 ;smoothing pan transition anoise rand ampdb(kdb), 2, 1 kbw = kcf/kq ;bandwidth of resonant filter abp reson anoise, kcf, kbw aout balance abp, anoise aL, aR pan2 aout, kp outs aL, aR endin </CsInstruments> <CsScore> i 1 0 5 i 2 5 5 e </CsScore> </CsoundSynthesizer>
The output should include lines like these:
WRITING: kcf = 1122.469723, kq = 11.762839, kdb = -14.313445, kpan = 0.538142 kcf = 1122.469723, kq = 11.762839, kdb = -14.313445, kpan = 0.538142 kcf = 1148.638412, kq = 12.040490, kdb = -14.061868, kpan = 0.552205 kcf = 165.796855, kq = 18.523179, kdb = -15.816977, kpan = 0.901528 kcf = 147.729960, kq = 13.071911, kdb = -11.924531, kpan = 0.982518 kcf = 497.430113, kq = 13.605512, kdb = -21.586611, kpan = 0.179229 READING: WARNING: Seeding from current time 3308160476 kcf = 1122.469700, kq = 11.762800, kdb = -14.313400, kpan = 0.538100 kcf = 1122.469700, kq = 11.762800, kdb = -14.313400, kpan = 0.538100 kcf = 1148.638400, kq = 12.040500, kdb = -14.061900, kpan = 0.552200 kcf = 165.796900, kq = 18.523200, kdb = -15.817000, kpan = 0.901500 kcf = 147.730000, kq = 13.071900, kdb = -11.924500, kpan = 0.982500 kcf = 497.430100, kq = 13.605500, kdb = -21.586600, kpan = 0.179200