wavetable oscillator with lanczos2 resampling

2026-07-26 04:55:39 -07:00
parent 3e41930e7d
commit 66bea462e7
4 changed files with 134 additions and 4 deletions
@@ -0,0 +1,23 @@
+# lanczos2 kernel interval -2:0
+# generating 512 point LUT
+# 511 is centerpoint
+
+# lanczos defined as sinc(x) * sinc(x/a)
+# a is order (2)
+# sinc(x) = sin(x) / x
+# output format:
+# 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 0xNNNN, 
+# x32 lines
+
+import numpy as np
+
+for j in range(0, 512, 16):
+    lineString = ""
+    for k in range(16):
+        i = j + k
+        x = (i - 511) / 256
+        y = np.sinc(x) * np.sinc(x / 2)
+        y *= 32767
+        lineString += hex(int(y))
+        lineString += ", "
+    print(lineString)