From 346245c4ccb57f4d26189b774dfc5e675b32267e Mon Sep 17 00:00:00 2001
From: Ahmet Inan <inan@aicodix.de>
Date: Mon, 27 Mar 2023 11:07:04 +0200
Subject: [PATCH] added simple interleavers

---
 interleave.hh | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 interleave.hh

diff --git a/interleave.hh b/interleave.hh
new file mode 100644
index 0000000..78c067e
--- /dev/null
+++ b/interleave.hh
@@ -0,0 +1,32 @@
+/*
+Interleavers
+
+Copyright 2023 Ahmet Inan <inan@aicodix.de>
+*/
+
+#pragma once
+
+namespace CODE {
+
+template <int SIZE, int ORDER, typename TYPE>
+static void Interleave(TYPE *out, const TYPE *in)
+{
+	static_assert(SIZE % ORDER == 0, "ORDER does not divide SIZE");
+	int LENGTH = SIZE / ORDER;
+	for (int i = 0; i < LENGTH; ++i)
+		for (int j = 0; j < ORDER; ++j)
+			out[ORDER*i+j] = in[i+j*LENGTH];
+}
+
+template <int SIZE, int ORDER, typename TYPE>
+static void Deinterleave(TYPE *out, const TYPE *in)
+{
+	static_assert(SIZE % ORDER == 0, "ORDER does not divide SIZE");
+	int LENGTH = SIZE / ORDER;
+	for (int i = 0; i < LENGTH; ++i)
+		for (int j = 0; j < ORDER; ++j)
+			out[i+j*LENGTH] = in[ORDER*i+j];
+}
+
+}
+