add byte manipulation functions

third-party/rsutils/include/rsutils/byte-manipulation.h

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+// License: Apache 2.0. See LICENSE file in root directory.
+// Copyright(c) 2023 Intel Corporation. All Rights Reserved.
+
+#pragma once
+
+namespace rsutils
+{
+    namespace byte
+    {
+        unsigned char reverse_bits(unsigned char b);
+        void reverse_byte_array_bits(unsigned char* byte_array, int size);
+    }
+}

third-party/rsutils/src/byte-manipulation.cpp

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+// License: Apache 2.0. See LICENSE file in root directory.
+// Copyright(c) 2024 Intel Corporation. All Rights Reserved.
+
+#include <rsutils/byte-manipulation.h>
+
+namespace rsutils
+{
+    namespace byte
+    {
+        // A helper function that takes a byte and reverses its bits
+        // e.g. intput: 00110101  output: 10101100
+
+        // First the left four bits are swapped with the right four bits.
+        // Then all adjacent pairs are swapped and then all adjacent single bits.
+        // This results in a reversed order.
+        unsigned char reverse_bits(unsigned char b)
+        {
+            b = (b & 0xF0) >> 4 | (b & 0x0F) << 4;
+            b = (b & 0xCC) >> 2 | (b & 0x33) << 2;
+            b = (b & 0xAA) >> 1 | (b & 0x55) << 1;
+            return b;
+        }
+
+        // A helper function that takes a byte rray of a given size,
+        // and reverses the bits order of for each byte of this array
+        // e.g. intput: byteArray = {byte0=00110101, byte1=11110000}, size = 2
+        // output: byteArray [ byte0=10101100, byte1=00001111]
+        void reverse_byte_array_bits(unsigned char* byte_array, int size) {
+            for (int i = 0; i < size; ++i)
+            {
+                byte_array[i] = reverse_bits(byte_array[i]);
+            }
+        }
+    }
+}
+