GEN01
Prev | Score Statements and GEN Routines | Next

## GEN01

GEN01 — Transfers data from a soundfile into a function table.

## Description

This subroutine transfers data from a soundfile into a function table.

## Syntax

    f#  time  size  1  filcod  skiptime  format  channel

## Performance

size -- number of points in the table. Ordinarily a power of 2 or a power-of-2 plus 1 (see f statement); the maximum tablesize is 16777216 (224) points. The allocation of table memory can be deferred by setting this parameter to 0; the size allocated is then the number of points in the file (probably not a power-of-2), and the table is not usable by normal oscillators, but it is usable by a loscil unit. The soundfile can also be mono or stereo.

filcod -- integer or character-string denoting the source soundfile name. An integer denotes the file soundin.filcod ; a character-string (in double quotes, spaces permitted) gives the filename itself, optionally a full pathname. If not a full path, the file is sought first in the current directory, then in that given by the environment variable SSDIR (if defined) then by SFDIR. See also soundin.

skiptime -- begin reading at skiptime seconds into the file.

channel -- channel number to read in. 0 denotes read all channels.

format -- specifies the audio data-file format:

1 - 8-bit signed character 4 - 16-bit short integers
2 - 8-bit A-law bytes 5 - 32-bit long integers
3 - 8-bit U-law bytes 6 - 32-bit floats

If format = 0 the sample format is taken from the soundfile header, or by default from the CSound -o command-line flag.

| Note

- Reading stops at end-of-file or when the table is full. Table locations not filled will contain zeros.

- If p4 is positive, the table will be post-normalized (rescaled to a maximum absolute value of 1 after generation). A negative p4 will cause rescaling to be skipped.

- GEN01 also works with WAV and OGG and a dozen and more other sound formats; these file formats depend on libsndfile, see http://www.mega-nerd.com/libsndfile/

## Examples

Here is an example of the GEN01 routine. It uses the files gen01.csd and several sound files.

Example 979. An example of the GEN01 routine.

    <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 gen01.wav -W ;;; for file output any platform
    </CsOptions>
    <CsInstruments>

    sr = 44100
    ksmps = 32
    nchnls = 2
    0dbfs  = 1

    instr 1	;plays deferred and non-deferred sounds with loscil

    ifn = p4
    ibas = 1

    asig loscil 1, 1, ifn, ibas
         outs asig, asig

    endin

    instr 2	;plays only non-deffered sound

    isnd  = p4
    aread line   sr*p3, p3, 0				;play this backward
    asig  tablei aread, isnd				;use table 1
          outs   asig, asig

    endin
    </CsInstruments>
    <CsScore>
    f 1 0 131072 1 "beats.wav" 0 0 0			;non-deferred sound
    f 2 0    0   1 "flute.aiff" 0 0 0			;& deferred sounds in
    f 3 0    0   1 "beats.ogg" 0 0 0			;different formats

    i 1 0 1 1
    i 1 + 1 2
    i 1 + 1 3

    i 2 4 2 1	;non-deffered sound for instr. 2
    e
    </CsScore>
    </CsoundSynthesizer>

These are the diagrams of the waveforms of the GEN01 routines, as used in the example:

f 1 0 131072 1 "beats.wav" 0 0 0 - non-deferred sound

f 2 0 0 1 "flute.aiff" 0 0 0 - deferred sound

f 3 0 0 1 "beats.ogg" 0 0 0 - deferred sound

## Credits

September 2003. Thanks goes to Dr. Richard Boulanger for pointing out the references to the AIFF file format.

Prev | Up | Next
GEN Routines | Home | GEN02