public void Dispose()
{
if (setup != IntPtr.Zero)
{
InteropWrapper.pffft_destroy_setup(setup);
setup = IntPtr.Zero;
InteropWrapper.pffft_aligned_free(alignedBuffer1);
InteropWrapper.pffft_aligned_free(alignedBuffer2);
}
}
private void Transform(float *input, float *output, Direction direction)
{
// The non-ordered transform pffft_transform may be faster,
// but all Aurio algorithms expect the canonical ordered form
InteropWrapper.pffft_transform_ordered(setup, input, output, null, direction);
// Scale backward transform by 1/N (according to docs)
if (direction == Direction.Backward)
{
for (int x = 0; x < size; x++)
{
output[x] /= size;
}
}
}
public PFFFT(int size, Transform transform)
{
if ((size * 4) % 16 != 0)
{
// For more info see pffft.h
throw new Exception("invalid size, must be aligned to a 16-byte boundary");
}
this.size = size;
setup = InteropWrapper.pffft_new_setup(size, transform);
if (size >= 16384)
{
Console.WriteLine("WARNING: size too large, might result in low performance");
// TODO if this ever gets a problem, implement a "work" area, see pffft.h @ pffft_transform
}
uint bufferByteSize = (uint)size * 4;
alignedBuffer1 = InteropWrapper.pffft_aligned_malloc(new UIntPtr(bufferByteSize));
alignedBuffer2 = InteropWrapper.pffft_aligned_malloc(new UIntPtr(bufferByteSize));
}