diff --git a/aegisub/endian.h b/aegisub/endian.h
new file mode 100644
index 000000000..ea01dbcc7
--- /dev/null
+++ b/aegisub/endian.h
@@ -0,0 +1,332 @@
+// Copyright (c) 2008, Niels Martin Hansen
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+//   * Redistributions of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//   * Redistributions in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//   * Neither the name of the Aegisub Group nor the names of its contributors
+//     may be used to endorse or promote products derived from this software
+//     without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// -----------------------------------------------------------------------------
+//
+// AEGISUB
+//
+// Website: http://www.aegisub.net
+// Contact: mailto:jiifurusu@gmail.com
+//
+
+#pragma once
+
+#ifndef _ENDIAN_H
+#define _ENDIAN_H
+
+
+// Sanity check
+
+#ifndef HAVE_LITTLE_ENDIAN
+#ifndef HAVE_BIG_ENDIAN
+#ifndef HAVE_DYNAMIC_ENDIAN
+#define HAVE_DYNAMIC_ENDIAN
+#endif
+#endif
+#endif
+
+#ifdef HAVE_LITTLE_ENDIAN
+#ifdef HAVE_BIG_ENDIAN
+#error You cannot have both HAVE_LITTLE_ENDIAN and HAVE_BIG_ENDIAN defined at the same time
+#endif
+#endif
+
+
+#include <stdint.h>
+
+
+namespace Endian {
+
+	// Unconditionally reverse endianness
+
+	// These are only defined for unsigned ints,
+	// Use reinterpret_cast on the values if you need signed values.
+
+	inline uint16_t Reverse(uint16_t val)
+	{
+		return
+			((val & 0x00FF) << 8) |
+			((val & 0xFF00) >> 8);
+	}
+
+	inline uint32_t Reverse(uint32_t val)
+	{
+		return
+			((val & 0x000000FF) << 24) |
+			((val & 0x0000FF00) <<  8) |
+			((val & 0x00FF0000) >>  8) |
+			((val & 0xFF000000) >> 24);
+	}
+
+	inline uint64_t Reverse(uint64_t val)
+	{
+		return
+			((val & 0x00000000000000FF) << 56) |
+			((val & 0x000000000000FF00) << 40) |
+			((val & 0x0000000000FF0000) << 24) |
+			((val & 0x00000000FF000000) <<  8) |
+			((val & 0x000000FF00000000) >>  8) |
+			((val & 0x0000FF0000000000) >> 24) |
+			((val & 0x00FF000000000000) >> 40) |
+			((val & 0xFF00000000000000) >> 56);
+	}
+
+
+#ifndef HAVE_DYNAMIC_ENDIAN
+
+
+	// Regular, fast, templatized conditional reversing
+
+	template <class T>
+	inline T LittleToMachine(T val)
+	{
+#ifdef HAVE_BIG_ENDIAN
+		// We're on big endian, reverse little to big
+		return Reverse(val);
+#else
+		// We're on little endian and input is little
+		return val;
+#endif
+	}
+
+	template <class T>
+	inline T BigToMachine(T val)
+	{
+#ifdef HAVE_LITTLE_ENDIAN
+		// We're on little endian, reverse big to little
+		return Reverse(val);
+#else
+		// We're on big endian and input is big
+		return val;
+#endif
+	}
+
+	template <class T>
+	inline T MachineToLittle(T val)
+	{
+#ifdef HAVE_BIG_ENDIAN
+		// We're on big endian, reverse to little
+		return Reverse(val);
+#else
+		// Already on little, nothing to be done
+		return val;
+#endif
+	}
+
+	template <class T>
+	inline T MachineToBig(T val)
+	{
+#ifdef HAVE_LITTLE_ENDIAN
+		// We're on little endian, reverse to big
+		return Reverse(val);
+#else
+		// Already on big, nothing to be done
+		return val;
+#endif
+	}
+
+
+#else
+
+
+	// Dynamic endianness handling
+
+	// Exploit that bit-shifting operations always can put bytes into
+	// machine word order, while unions can be used to access bytes
+	// only from an explicitly given byte order.
+	// This is probably slower than when we explicitly know
+	// the endianness of the machine we are on, but it's the same
+	// code for any platform!
+
+
+	// Unions to pack together ints and get their physical bytes
+
+	union bytes16 {
+		uint8_t byte[2];
+		uint16_t word;
+	};
+	union bytes32 {
+		uint8_t byte[4];
+		uint32_t word;
+	};
+	union bytes64 {
+		uint8_t byte[8];
+		uint64_t word;
+	};
+
+
+	// 16 bit words
+
+	uint16_t MachineToBig(uint16_t val)
+	{
+		bytes16 pack;
+		// Store the bytes into the correct positions in the word
+		pack.byte[0] = (val & 0xFF00) >> 8;
+		pack.byte[1] = val & 0x00FF;
+		// And return a value now encoded as big endian
+		return pack.word;
+	}
+
+	uint16_t MachineToLittle(uint16_t val)
+	{
+		bytes16 pack;
+		// Store the bytes into the correct positions in the word
+		pack.byte[0] = val & 0x00FF;
+		pack.byte[1] = (val & 0xFF00) >> 8;
+		// And return a value now encoded as little endian
+		return pack.word;
+	}
+
+	uint16_t BigToMachine(uint16_t val)
+	{
+		bytes16 pack;
+		// Put our word into the pack
+		pack.word = val;
+		// And produce a machine endian value of it
+		return uint16_t(pack.byte[1]) | (uint16_t(pack.byte[0]) << 8);
+	}
+
+	uint16_t LittleToMachine(uint16_t val)
+	{
+		bytes16 pack;
+		// Put our word into the pack
+		pack.word = val;
+		// And produce a machine endian value of it
+		return uint16_t(pack.byte[0]) | (uint16_t(pack.byte[1]) << 8);
+	}
+
+
+	// 32 bit words
+
+	uint32_t MachineToBig(uint32_t val)
+	{
+		bytes32 pack;
+		pack.byte[0] = (val & 0xFF000000) >> 24;
+		pack.byte[1] = (val & 0x00FF0000) >> 16;
+		pack.byte[2] = (val & 0x0000FF00) >>  8;
+		pack.byte[3] =  val & 0x000000FF       ;
+		return pack.word;
+	}
+
+	uint32_t MachineToLittle(uint32_t val)
+	{
+		bytes32 pack;
+		pack.byte[0] =  val & 0x000000FF       ;
+		pack.byte[1] = (val & 0x0000FF00) >>  8;
+		pack.byte[2] = (val & 0x00FF0000) >> 16;
+		pack.byte[3] = (val & 0xFF000000) >> 24;
+		return pack.word;
+	}
+
+	uint32_t BigToMachine(uint32_t val)
+	{
+		bytes32 pack;
+		pack.word = val;
+		return
+			(uint32_t(pack.byte[0]) << 24) |
+			(uint32_t(pack.byte[1]) << 16) |
+			(uint32_t(pack.byte[2]) <<  8) |
+			 uint32_t(pack.byte[3]);
+	}
+
+	uint32_t LittleToMachine(uint32_t val)
+	{
+		bytes32 pack;
+		pack.word = val;
+		return
+			(uint32_t(pack.byte[3]) << 24) |
+			(uint32_t(pack.byte[2]) << 16) |
+			(uint32_t(pack.byte[1]) <<  8) |
+			 uint32_t(pack.byte[0]);
+	}
+
+
+	// 64 bit words
+
+	uint64_t MachineToBig(uint64_t val)
+	{
+		bytes64 pack;
+		pack.byte[0] = (val & 0xFF00000000000000) >> 56;
+		pack.byte[1] = (val & 0x00FF000000000000) >> 48;
+		pack.byte[2] = (val & 0x0000FF0000000000) >> 40;
+		pack.byte[3] = (val & 0x000000FF00000000) >> 32;
+		pack.byte[4] = (val & 0x00000000FF000000) >> 24;
+		pack.byte[5] = (val & 0x0000000000FF0000) >> 16;
+		pack.byte[6] = (val & 0x000000000000FF00) >>  8;
+		pack.byte[7] =  val & 0x00000000000000FF       ;
+		return pack.word;
+	}
+
+	uint64_t MachineToLittle(uint64_t val)
+	{
+		bytes64 pack;
+		pack.byte[0] =  val & 0x00000000000000FF       ;
+		pack.byte[1] = (val & 0x000000000000FF00) >>  8;
+		pack.byte[2] = (val & 0x0000000000FF0000) >> 16;
+		pack.byte[3] = (val & 0x00000000FF000000) >> 24;
+		pack.byte[4] = (val & 0x000000FF00000000) >> 32;
+		pack.byte[5] = (val & 0x0000FF0000000000) >> 40;
+		pack.byte[6] = (val & 0x00FF000000000000) >> 48;
+		pack.byte[7] = (val & 0xFF00000000000000) >> 56;
+		return pack.word;
+	}
+
+	uint64_t BigToMachine(uint64_t val)
+	{
+		bytes64 pack;
+		pack.word = val;
+		return
+			(uint32_t(pack.byte[0]) << 56) |
+			(uint32_t(pack.byte[1]) << 48) |
+			(uint32_t(pack.byte[2]) << 40) |
+			(uint32_t(pack.byte[3]) << 32) |
+			(uint32_t(pack.byte[4]) << 24) |
+			(uint32_t(pack.byte[5]) << 16) |
+			(uint32_t(pack.byte[6]) <<  8) |
+			 uint32_t(pack.byte[7]);
+	}
+
+	uint64_t LittleToMachine(uint64_t val)
+	{
+		bytes64 pack;
+		pack.word = val;
+		return
+			(uint32_t(pack.byte[7]) << 56) |
+			(uint32_t(pack.byte[6]) << 48) |
+			(uint32_t(pack.byte[5]) << 40) |
+			(uint32_t(pack.byte[4]) << 32) |
+			(uint32_t(pack.byte[3]) << 24) |
+			(uint32_t(pack.byte[2]) << 16) |
+			(uint32_t(pack.byte[1]) <<  8) |
+			 uint32_t(pack.byte[0]);
+	}
+
+
+#endif
+
+};
+
+#endif
diff --git a/aegisub/win32/config0.h b/aegisub/win32/config0.h
index 4565ebbe0..3f32af01c 100644
--- a/aegisub/win32/config0.h
+++ b/aegisub/win32/config0.h
@@ -43,6 +43,11 @@
 #endif
 
 
+// Endianness: We don't support any Windows version that runs on big endian
+#define HAVE_LITTLE_ENDIAN
+#undef HAVE_BIG_ENDIAN
+
+
 ////////////// HIGH PRIORITY /////////////
 
 // Enable Automation
diff --git a/aegisub/win64/config0.h b/aegisub/win64/config0.h
index b7f0920c8..55922db43 100644
--- a/aegisub/win64/config0.h
+++ b/aegisub/win64/config0.h
@@ -43,6 +43,11 @@
 #endif
 
 
+// Endianness: We don't support any Windows version that runs on big endian
+#define HAVE_LITTLE_ENDIAN
+#undef HAVE_BIG_ENDIAN
+
+
 ////////////// HIGH PRIORITY /////////////
 
 // Enable Automation