glintResample function

Float32List glintResample(Float32List pcm, int channels, int srIn, int srOut,)

Resample interleaved float PCM (±1.0) from srIn to srOut with a Kaiser-windowed sinc kernel (anti-aliased, unity passband). pcm is frames * channels interleaved samples. Pass-through (a copy) when the rates match.

Implementation

Float32List glintResample(Float32List pcm, int channels, int srIn, int srOut) {
  if (channels <= 0 || pcm.isEmpty) return Float32List(0);
  final lib = _loadLibrary();
  final fn = lib.lookupFunction<_ResampleNative, _Resample>('glint_resample');
  final free = lib.lookupFunction<_FreeNative, _Free>('glint_free');
  final inPtr = calloc<Float>(pcm.length);
  inPtr.asTypedList(pcm.length).setAll(0, pcm);
  final outFrames = calloc<Int32>();
  try {
    final inFrames = pcm.length ~/ channels;
    final ptr = fn(inPtr, inFrames, channels, srIn, srOut, outFrames);
    if (ptr == nullptr) return Float32List(0);
    final total = outFrames.value * channels;
    final out = Float32List.fromList(ptr.asTypedList(total));
    free(ptr.cast<Void>());
    return out;
  } finally {
    calloc.free(inPtr);
    calloc.free(outFrames);
  }
}