_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
- _MEM, _MEMSOUND, _MEMFREE
- _MEMPUT, _MEMGET, _MEMGET (function)
- _SNDOPEN, _SNDCLOSE, _SNDRAW, _SNDRATE