_SNDNEW
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The _SNDNEW function creates a raw empty sound in memory and returns a LONG handle value above 0. The sound's raw memory can then be accessed using _MEMSOUND, _MEMGET (function) & _MEMPUT.
Syntax
- soundHandle& = _SNDNEW(frames&, channels&, bits&)
Parameters
- frames& is the number of sample frames needed.
- 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 the function to create a raw sound in memory.
- Once the sound is created, it can then be accessed using _MEMSOUND, _MEMGET (function) & _MEMPUT.
- Using this one can generate sounds once programmatically and play it multiple times.
- The sound memory can also be filled with sample data from other sources like files, DATA statements and more!
- Sound handle values and the memory used must be freed using _SNDCLOSE when no longer required.
- A sample rate (_SNDRATE) of 48000 means 48000 sample frames / second.
- 1 sample frame = 1 sample x number of channels.
Availability
- QBPE 3.5 and up (QB64 Phoenix Edition)
Examples
Example 1: Creating a sound at runtime and playing it.
$CONSOLE OPTION _EXPLICIT OPTION _EXPLICITARRAY 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 |