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Whoops, that was Blackman-Harris, not Lanczos. Lanczos produces less aliasing, anyway.

--- a/dumb/src/helpers/lanczos_resampler.c

+++ b/dumb/src/helpers/lanczos_resampler.c

@@ -33,7 +33,7 @@

 		cosine_lut[i] = (1.0 - cos(((double)(i) / COSINE_RESOLUTION) * M_PI)) * 0.5;

 	dx = (double)(LANCZOS_WIDTH) / LANCZOS_SAMPLES; x = 0.0;

 	for (i = 0; i < LANCZOS_SAMPLES; ++i, x += dx)

-		lanczos_lut[i] = abs(x) < LANCZOS_WIDTH ? sinc(x) * (0.35875 + 0.48829 * cos((M_PI * x) / 3) + 0.14128 * cos((2 * M_PI * x) / 3) + 0.01168 * cos(M_PI * x)) : 0.0;

+		lanczos_lut[i] = abs(x) < LANCZOS_WIDTH ? sinc(x) * sinc(x / LANCZOS_WIDTH) : 0.0;

 }

 typedef struct lanczos_resampler