_SNDNEW

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The _SNDNEW function creates a raw empty sound in memory and returns a LONG handle value for later access.


Syntax

soundHandle& = _SNDNEW(frames&, channels&, bits&)


Parameters

  • frames& is the number of sample frames needed. The number needed for one second of sound is determined by your sound hardware's sample rate, hence you may use the following formula:
    • frames& = _SNDRATE * neededSeconds! where you may also specify fractional seconds.
  • channels& is the number of channels needed (1 = mono, 2 = stereo).
  • bits& is the number of bits per channel (8 = 8-bit unsigned integer, 16 = 16-bit signed integer, 32 = 32-bit floating point).


Description

  • Use this function to create a raw sound in memory.
  • Once the sound is created, it can be accessed and manipulated using the _MEM interface statements and functions, mainly _MEMSOUND, _MEMGET & _MEMPUT.
  • Using this function can generate sounds once programmatically and then play it multiple times.
  • The sound memory can also be filled with sample data from other sources like files, DATA statements and more.
  • Sound block pointers obtained with _MEMSOUND must be freed using _MEMFREE and the returned Sound handle value must be freed using _SNDCLOSE when no longer required.


Availability

  • QBPE 3.5 and up (QB64 Phoenix Edition)


Examples

Example 1
Creating a sound at runtime and playing it.
$CONSOLE
OPTION _EXPLICIT

RANDOMIZE TIMER

CONST SOUND_DURATION = 5 ' duration is seconds
CONST SAMPLE_CHANNELS = 1 ' number of channes. For stereo we need to add another _MEMPUT below and +offset by SAMPLE_BYTES
CONST SAMPLE_BYTES = 4 ' number of bytes / sample (not frame!)

DIM h AS LONG: h = _SNDNEW(SOUND_DURATION * _SNDRATE, SAMPLE_CHANNELS, SAMPLE_BYTES * 8)
IF (h < 1) THEN
    PRINT "Failed to create sound!"
    END
END IF

DIM sndblk AS _MEM: sndblk = _MEMSOUND(h, 0)
IF sndblk.SIZE = 0 THEN
    _SNDCLOSE h
    PRINT "Failed to access sound data!"
    END
END IF

DIM t AS _INTEGER64
FOR t = 0 TO (SOUND_DURATION * _SNDRATE) - 1
    _MEMPUT sndblk, sndblk.OFFSET + (t * SAMPLE_BYTES * SAMPLE_CHANNELS), SIN(2 * _PI * 440 * t / _SNDRATE) + RND - RND AS SINGLE ' mixes noise and a sine wave
NEXT

_SNDPLAY h

SLEEP SOUND_DURATION

_SNDCLOSE h

END


See also



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