diff --git a/Source/Core/VideoBackends/D3D/main.cpp b/Source/Core/VideoBackends/D3D/main.cpp
index 9bd7b685f1..babdfc4059 100644
--- a/Source/Core/VideoBackends/D3D/main.cpp
+++ b/Source/Core/VideoBackends/D3D/main.cpp
@@ -186,7 +186,7 @@ void VideoBackend::Video_Prepare()
 	Fifo::Init();
 	IndexGenerator::Init();
 	VertexLoaderManager::Init();
-	OpcodeDecoder_Init();
+	OpcodeDecoder::Init();
 	VertexShaderManager::Init();
 	PixelShaderManager::Init();
 	GeometryShaderManager::Init();
@@ -211,7 +211,7 @@ void VideoBackend::Shutdown()
 		GeometryShaderManager::Shutdown();
 		PixelShaderManager::Shutdown();
 		VertexShaderManager::Shutdown();
-		OpcodeDecoder_Shutdown();
+		OpcodeDecoder::Shutdown();
 		VertexLoaderManager::Shutdown();
 
 		// internal interfaces
diff --git a/Source/Core/VideoBackends/OGL/main.cpp b/Source/Core/VideoBackends/OGL/main.cpp
index 07648b6acd..c4698d28d6 100644
--- a/Source/Core/VideoBackends/OGL/main.cpp
+++ b/Source/Core/VideoBackends/OGL/main.cpp
@@ -181,8 +181,8 @@ void VideoBackend::Video_Prepare()
 	BPInit();
 	g_vertex_manager = std::make_unique<VertexManager>();
 	g_perf_query = GetPerfQuery();
-	Fifo::Init(); // must be done before OpcodeDecoder_Init()
-	OpcodeDecoder_Init();
+	Fifo::Init(); // must be done before OpcodeDecoder::Init()
+	OpcodeDecoder::Init();
 	IndexGenerator::Init();
 	VertexShaderManager::Init();
 	PixelShaderManager::Init();
@@ -233,7 +233,7 @@ void VideoBackend::Video_Cleanup()
 	g_perf_query.reset();
 	g_vertex_manager.reset();
 
-	OpcodeDecoder_Shutdown();
+	OpcodeDecoder::Shutdown();
 	g_renderer.reset();
 	GLInterface->ClearCurrent();
 }
diff --git a/Source/Core/VideoBackends/Software/SWmain.cpp b/Source/Core/VideoBackends/Software/SWmain.cpp
index 16d80df52f..e229a713e4 100644
--- a/Source/Core/VideoBackends/Software/SWmain.cpp
+++ b/Source/Core/VideoBackends/Software/SWmain.cpp
@@ -205,7 +205,7 @@ void VideoSoftware::Video_Cleanup()
 		PixelShaderManager::Shutdown();
 		g_perf_query.reset();
 		g_vertex_manager.reset();
-		OpcodeDecoder_Shutdown();
+		OpcodeDecoder::Shutdown();
 		g_renderer.reset();
 	}
 }
@@ -221,8 +221,8 @@ void VideoSoftware::Video_Prepare()
 	BPInit();
 	g_vertex_manager = std::make_unique<SWVertexLoader>();
 	g_perf_query = std::make_unique<PerfQuery>();
-	Fifo::Init(); // must be done before OpcodeDecoder_Init()
-	OpcodeDecoder_Init();
+	Fifo::Init(); // must be done before OpcodeDecoder::Init()
+	OpcodeDecoder::Init();
 	IndexGenerator::Init();
 	VertexShaderManager::Init();
 	PixelShaderManager::Init();
diff --git a/Source/Core/VideoCommon/Fifo.cpp b/Source/Core/VideoCommon/Fifo.cpp
index acc43b8855..506024c193 100644
--- a/Source/Core/VideoCommon/Fifo.cpp
+++ b/Source/Core/VideoCommon/Fifo.cpp
@@ -261,7 +261,7 @@ static void ReadDataFromFifoOnCPU(u32 readPtr)
 		}
 	}
 	Memory::CopyFromEmu(s_video_buffer_write_ptr, readPtr, len);
-	s_video_buffer_pp_read_ptr = OpcodeDecoder_Run<true>(DataReader(s_video_buffer_pp_read_ptr, write_ptr + len), nullptr, false);
+	s_video_buffer_pp_read_ptr = OpcodeDecoder::Run<true>(DataReader(s_video_buffer_pp_read_ptr, write_ptr + len), nullptr, false);
 	// This would have to be locked if the GPU thread didn't spin.
 	s_video_buffer_write_ptr = write_ptr + len;
 }
@@ -305,7 +305,7 @@ void RunGpuLoop()
 			// See comment in SyncGPU
 			if (write_ptr > seen_ptr)
 			{
-				s_video_buffer_read_ptr = OpcodeDecoder_Run(DataReader(s_video_buffer_read_ptr, write_ptr), nullptr, false);
+				s_video_buffer_read_ptr = OpcodeDecoder::Run(DataReader(s_video_buffer_read_ptr, write_ptr), nullptr, false);
 				s_video_buffer_seen_ptr = write_ptr;
 			}
 		}
@@ -336,7 +336,7 @@ void RunGpuLoop()
 					"Negative fifo.CPReadWriteDistance = %i in FIFO Loop !\nThat can produce instability in the game. Please report it.", fifo.CPReadWriteDistance - 32);
 
 				u8* write_ptr = s_video_buffer_write_ptr;
-				s_video_buffer_read_ptr = OpcodeDecoder_Run(DataReader(s_video_buffer_read_ptr, write_ptr), &cyclesExecuted, false);
+				s_video_buffer_read_ptr = OpcodeDecoder::Run(DataReader(s_video_buffer_read_ptr, write_ptr), &cyclesExecuted, false);
 
 				Common::AtomicStore(fifo.CPReadPointer, readPtr);
 				Common::AtomicAdd(fifo.CPReadWriteDistance, -32);
@@ -423,7 +423,7 @@ void RunGpu()
 					reset_simd_state = true;
 				}
 				ReadDataFromFifo(fifo.CPReadPointer);
-				s_video_buffer_read_ptr = OpcodeDecoder_Run(DataReader(s_video_buffer_read_ptr, s_video_buffer_write_ptr), nullptr, false);
+				s_video_buffer_read_ptr = OpcodeDecoder::Run(DataReader(s_video_buffer_read_ptr, s_video_buffer_write_ptr), nullptr, false);
 			}
 
 			//DEBUG_LOG(COMMANDPROCESSOR, "Fifo wraps to base");
diff --git a/Source/Core/VideoCommon/OpcodeDecoding.cpp b/Source/Core/VideoCommon/OpcodeDecoding.cpp
index 99a801a8f3..3af3337b9e 100644
--- a/Source/Core/VideoCommon/OpcodeDecoding.cpp
+++ b/Source/Core/VideoCommon/OpcodeDecoding.cpp
@@ -28,8 +28,11 @@
 #include "VideoCommon/VideoCommon.h"
 #include "VideoCommon/XFMemory.h"
 
-
 bool g_bRecordFifoData = false;
+
+namespace OpcodeDecoder
+{
+
 static bool s_bFifoErrorSeen = false;
 
 static u32 InterpretDisplayList(u32 address, u32 size)
@@ -49,7 +52,7 @@ static u32 InterpretDisplayList(u32 address, u32 size)
 		// temporarily swap dl and non-dl (small "hack" for the stats)
 		Statistics::SwapDL();
 
-		OpcodeDecoder_Run(DataReader(startAddress, startAddress + size), &cycles, true);
+		Run(DataReader(startAddress, startAddress + size), &cycles, true);
 		INCSTAT(stats.thisFrame.numDListsCalled);
 
 		// un-swap
@@ -67,7 +70,7 @@ static void InterpretDisplayListPreprocess(u32 address, u32 size)
 
 	if (startAddress != nullptr)
 	{
-		OpcodeDecoder_Run<true>(DataReader(startAddress, startAddress + size), nullptr, true);
+		Run<true>(DataReader(startAddress, startAddress + size), nullptr, true);
 	}
 }
 
@@ -120,18 +123,17 @@ static void UnknownOpcode(u8 cmd_byte, void *buffer, bool preprocess)
 	}
 }
 
-void OpcodeDecoder_Init()
+void Init()
 {
 	s_bFifoErrorSeen = false;
 }
 
-
-void OpcodeDecoder_Shutdown()
+void Shutdown()
 {
 }
 
 template <bool is_preprocess>
-u8* OpcodeDecoder_Run(DataReader src, u32* cycles, bool in_display_list)
+u8* Run(DataReader src, u32* cycles, bool in_display_list)
 {
 	u32 totalCycles = 0;
 	u8* opcodeStart;
@@ -314,5 +316,7 @@ end:
 	return opcodeStart;
 }
 
-template u8* OpcodeDecoder_Run<true>(DataReader src, u32* cycles, bool in_display_list);
-template u8* OpcodeDecoder_Run<false>(DataReader src, u32* cycles, bool in_display_list);
+template u8* Run<true>(DataReader src, u32* cycles, bool in_display_list);
+template u8* Run<false>(DataReader src, u32* cycles, bool in_display_list);
+
+} // namespace OpcodeDecoder
diff --git a/Source/Core/VideoCommon/OpcodeDecoding.h b/Source/Core/VideoCommon/OpcodeDecoding.h
index a79bf54be2..f955ecb90a 100644
--- a/Source/Core/VideoCommon/OpcodeDecoding.h
+++ b/Source/Core/VideoCommon/OpcodeDecoding.h
@@ -38,8 +38,13 @@
 #define GX_DRAW_LINE_STRIP          0x6   // 0xB0
 #define GX_DRAW_POINTS              0x7   // 0xB8
 
-void OpcodeDecoder_Init();
-void OpcodeDecoder_Shutdown();
+namespace OpcodeDecoder
+{
+
+void Init();
+void Shutdown();
 
 template <bool is_preprocess = false>
-u8* OpcodeDecoder_Run(DataReader src, u32* cycles, bool in_display_list);
+u8* Run(DataReader src, u32* cycles, bool in_display_list);
+
+} // namespace OpcodeDecoder