0dbfs
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## 0dbfs

0dbfs — Sets the value of 0 decibels using full scale amplitude.

## Description

Sets the value of 0 decibels using full scale amplitude.

## Syntax

    0dbfs = iarg

                0dbfs

## Initialization

iarg -- the value of 0 decibels using full scale amplitude.

## Performance

The default is 32767, so all existing orcs should work.

These calls should all work:

    ipeak = 0dbfs

    asig oscil 0dbfs,freq,1
    out  asig * 0.3 * 0dbfs

and so on.

As for documentation: the usage should be obvious - the main thing is for people to start to code 0dbfs-relatively (and use the ampdbfs() opcodes a lot more!), rather than use explicit sample values.

Floats written to a file, when 0dbfs = 1, will in effect go through no range translation at all. So the nunbers in the file are exactly what the orc says they are.

| BIG NB
All the main sample formats are supported, but I haven't got around to dealing with the char formats. Probably it's straight-forward... I have tried to cover the main utils - adsyn,lpanal etc. But there are bound to be things missing, sorry. Some of the parsing code is a bit grungy because I have a variable with a leading digit!

## Examples

Here is an example of the 0dbfs opcode. It uses the file 0dbfs.csd.

Example 20. Example of the 0dbfs 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
    ; Audio out   Audio in    No messages
    -odac           -iadc     -d     ;;;RT audio I/O
    ; For Non-realtime ouput leave only the line below:
    ; -o 0dbfs.wav -W ;;; for file output any platform
    </CsOptions>
    <CsInstruments>

    ; Initialize the global variables.
    sr = 44100
    kr = 4410
    ksmps = 10
    nchnls = 1

    ; Set the 0dbfs to the 16-bit maximum.
    0dbfs = 32767

    ; Instrument #1.
    instr 1
      ; Linearly increase the amplitude value "kamp" from
      ; 0 to 1 over the duration defined by p3.
      kamp line 0, p3, 1

      ; Generate a basic tone using our amplitude value.
      a1 oscil kamp, 440, 1

      ; Multiply the basic tone (with its amplitude between
      ; 0 and 1) by the full-scale 0dbfs value.
      out a1 * 0dbfs
    endin

    </CsInstruments>
    <CsScore>

    ; Table #1, a sine wave.
    f 1 0 16384 10 1

    ; Play Instrument #1 for three seconds.
    i 1 0 3
    e

    </CsScore>
    </CsoundSynthesizer>

Here is another example of the 0dbfs opcode. It uses the file 0dbfs.csd. This example has exactly the same output as the previous example, but output samples should now be normalized between -1 and 1.

Example 21. Example of the 0dbfs opcode with maximum amplitude of 1.

    <CsoundSynthesizer>
    <CsOptions>
    ; Select audio/midi flags here according to platform
    ; Audio out   Audio in    No messages
    -odac           -iadc     -d     ;;;RT audio I/O
    ; For Non-realtime ouput leave only the line below:
    ; -o 0dbfs.wav -W ;;; for file output any platform
    </CsOptions>
    <CsInstruments>

    ; Initialize the global variables.
    sr = 44100
    kr = 4410
    ksmps = 10
    nchnls = 1

    ; Set the 0dbfs to 1.
    0dbfs = 1

    ; Instrument #1.
    instr 1
      ; Linearly increase the amplitude value "kamp" from
      ; -90 to p4 (in dBfs) over the duration defined by p3.
      kamp line -90, p3, p4
      print ampdbfs(p4)
      ; Generate a basic tone using our amplitude value.
    a1 oscil ampdbfs(kamp), 440, 1

      ; Since 0dbfs = 1 we don't need to multiply the output
      out a1
    endin

    </CsInstruments>
    <CsScore>

    ; Table #1, a sine wave.
    f 1 0 16384 10 1

    ; Play Instrument #1 for three seconds.
    i 1 0 3 -6
    e

    </CsScore>
    </CsoundSynthesizer>

## See also

ampdbfs()

## Credits

Author: Richard Dobson
May 2002

Example written by Kevin Conder.

New in version 4.20

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