diff --git a/src/color.cc b/src/color.cc
index 75f81e8..6676720 100644
--- a/src/color.cc
+++ b/src/color.cc
@@ -7,35 +7,47 @@
 
 #include <algorithm>
 
+static int colorPaletteFileOpen(const char* filePath, int flags);
+static int colorPaletteFileRead(int fd, void* buffer, size_t size);
+static int colorPaletteFileClose(int fd);
+static void* colorPaletteMallocDefaultImpl(size_t size);
+static void* colorPaletteReallocDefaultImpl(void* ptr, size_t size);
+static void colorPaletteFreeDefaultImpl(void* ptr);
+static void _setIntensityTableColor(int a1);
+static void _setIntensityTables();
+static void _setMixTableColor(int a1);
+static void _buildBlendTable(unsigned char* ptr, unsigned char ch);
+static void _rebuildColorBlendTables();
+
 // 0x50F930
-char _aColor_cNoError[] = "color.c: No errors\n";
+static char _aColor_cNoError[] = "color.c: No errors\n";
 
 // 0x50F95C
-char _aColor_cColorTa[] = "color.c: color table not found\n";
+static char _aColor_cColorTa[] = "color.c: color table not found\n";
 
 // 0x51DF10
-char* _errorStr = _aColor_cNoError;
+static char* _errorStr = _aColor_cNoError;
 
 // 0x51DF14
-bool _colorsInited = false;
+static bool _colorsInited = false;
 
 // 0x51DF18
-double gBrightness = 1.0;
+static double gBrightness = 1.0;
 
 // 0x51DF20
-ColorTransitionCallback* gColorPaletteTransitionCallback = NULL;
+static ColorTransitionCallback* gColorPaletteTransitionCallback = NULL;
 
 // 0x51DF24
-MallocProc* gColorPaletteMallocProc = colorPaletteMallocDefaultImpl;
+static MallocProc* gColorPaletteMallocProc = colorPaletteMallocDefaultImpl;
 
 // 0x51DF28
-ReallocProc* gColorPaletteReallocProc = colorPaletteReallocDefaultImpl;
+static ReallocProc* gColorPaletteReallocProc = colorPaletteReallocDefaultImpl;
 
 // 0x51DF2C
-FreeProc* gColorPaletteFreeProc = colorPaletteFreeDefaultImpl;
+static FreeProc* gColorPaletteFreeProc = colorPaletteFreeDefaultImpl;
 
 // 0x51DF30
-ColorFileNameManger* gColorFileNameMangler = NULL;
+static ColorFileNameManger* gColorFileNameMangler = NULL;
 
 // 0x51DF34
 unsigned char _cmap[768] = {
@@ -67,18 +79,18 @@ unsigned char _colorMixMulTable[65536];
 unsigned char _colorTable[32768];
 
 // 0x6AB928
-ColorPaletteFileReadProc* gColorPaletteFileReadProc;
+static ColorPaletteFileReadProc* gColorPaletteFileReadProc;
 
 // 0x6AB92C
-ColorPaletteCloseProc* gColorPaletteFileCloseProc;
+static ColorPaletteCloseProc* gColorPaletteFileCloseProc;
 
 // 0x6AB930
-ColorPaletteFileOpenProc* gColorPaletteFileOpenProc;
+static ColorPaletteFileOpenProc* gColorPaletteFileOpenProc;
 
 // NOTE: Inlined.
 //
 // 0x4C7200
-int colorPaletteFileOpen(const char* filePath, int flags)
+static int colorPaletteFileOpen(const char* filePath, int flags)
 {
     if (gColorPaletteFileOpenProc != NULL) {
         return gColorPaletteFileOpenProc(filePath, flags);
@@ -90,7 +102,7 @@ int colorPaletteFileOpen(const char* filePath, int flags)
 // NOTE: Inlined.
 //
 // 0x4C7218
-int colorPaletteFileRead(int fd, void* buffer, size_t size)
+static int colorPaletteFileRead(int fd, void* buffer, size_t size)
 {
     if (gColorPaletteFileReadProc != NULL) {
         return gColorPaletteFileReadProc(fd, buffer, size);
@@ -102,7 +114,7 @@ int colorPaletteFileRead(int fd, void* buffer, size_t size)
 // NOTE: Inlined.
 //
 // 0x4C7230
-int colorPaletteFileClose(int fd)
+static int colorPaletteFileClose(int fd)
 {
     if (gColorPaletteFileCloseProc != NULL) {
         return gColorPaletteFileCloseProc(fd);
@@ -120,19 +132,19 @@ void colorPaletteSetFileIO(ColorPaletteFileOpenProc* openProc, ColorPaletteFileR
 }
 
 // 0x4C725C
-void* colorPaletteMallocDefaultImpl(size_t size)
+static void* colorPaletteMallocDefaultImpl(size_t size)
 {
     return malloc(size);
 }
 
 // 0x4C7264
-void* colorPaletteReallocDefaultImpl(void* ptr, size_t size)
+static void* colorPaletteReallocDefaultImpl(void* ptr, size_t size)
 {
     return realloc(ptr, size);
 }
 
 // 0x4C726C
-void colorPaletteFreeDefaultImpl(void* ptr)
+static void colorPaletteFreeDefaultImpl(void* ptr)
 {
     free(ptr);
 }
@@ -225,7 +237,7 @@ void _setSystemPaletteEntries(unsigned char* palette, int start, int end)
 }
 
 // 0x4C7550
-void _setIntensityTableColor(int a1)
+static void _setIntensityTableColor(int a1)
 {
     int v1, v2, v3, v4, v5, v6, v7, v8, v9, v10;
 
@@ -252,7 +264,7 @@ void _setIntensityTableColor(int a1)
 }
 
 // 0x4C7658
-void _setIntensityTables()
+static void _setIntensityTables()
 {
     for (int index = 0; index < 256; index++) {
         if (_mappedColor[index] != 0) {
@@ -264,7 +276,7 @@ void _setIntensityTables()
 }
 
 // 0x4C769C
-void _setMixTableColor(int a1)
+static void _setMixTableColor(int a1)
 {
     int i;
     int v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19;
@@ -436,7 +448,7 @@ char* _colorError()
 }
 
 // 0x4C7B44
-void _buildBlendTable(unsigned char* ptr, unsigned char ch)
+static void _buildBlendTable(unsigned char* ptr, unsigned char ch)
 {
     int r, g, b;
     int i, j;
@@ -496,7 +508,7 @@ void _buildBlendTable(unsigned char* ptr, unsigned char ch)
 }
 
 // 0x4C7D90
-void _rebuildColorBlendTables()
+static void _rebuildColorBlendTables()
 {
     int i;
 
diff --git a/src/color.h b/src/color.h
index 9ddf65d..1a4fe04 100644
--- a/src/color.h
+++ b/src/color.h
@@ -3,8 +3,6 @@
 
 #include "memory_defs.h"
 
-#include <stdlib.h>
-
 typedef const char*(ColorFileNameManger)(const char*);
 typedef void(ColorTransitionCallback)();
 
@@ -12,17 +10,6 @@ typedef int(ColorPaletteFileOpenProc)(const char* path, int mode);
 typedef int(ColorPaletteFileReadProc)(int fd, void* buffer, size_t size);
 typedef int(ColorPaletteCloseProc)(int fd);
 
-extern char _aColor_cNoError[];
-extern char _aColor_cColorTa[];
-
-extern char* _errorStr;
-extern bool _colorsInited;
-extern double gBrightness;
-extern ColorTransitionCallback* gColorPaletteTransitionCallback;
-extern MallocProc* gColorPaletteMallocProc;
-extern ReallocProc* gColorPaletteReallocProc;
-extern FreeProc* gColorPaletteFreeProc;
-extern ColorFileNameManger* gColorFileNameMangler;
 extern unsigned char _cmap[768];
 
 extern unsigned char _systemCmap[256 * 3];
@@ -33,17 +20,8 @@ extern unsigned char _colorMixAddTable[65536];
 extern unsigned char _intensityColorTable[65536];
 extern unsigned char _colorMixMulTable[65536];
 extern unsigned char _colorTable[32768];
-extern ColorPaletteFileReadProc* gColorPaletteFileReadProc;
-extern ColorPaletteCloseProc* gColorPaletteFileCloseProc;
-extern ColorPaletteFileOpenProc* gColorPaletteFileOpenProc;
 
-int colorPaletteFileOpen(const char* filePath, int flags);
-int colorPaletteFileRead(int fd, void* buffer, size_t size);
-int colorPaletteFileClose(int fd);
 void colorPaletteSetFileIO(ColorPaletteFileOpenProc* openProc, ColorPaletteFileReadProc* readProc, ColorPaletteCloseProc* closeProc);
-void* colorPaletteMallocDefaultImpl(size_t size);
-void* colorPaletteReallocDefaultImpl(void* ptr, size_t size);
-void colorPaletteFreeDefaultImpl(void* ptr);
 int _calculateColor(int a1, int a2);
 int _Color2RGB_(int a1);
 void colorPaletteFadeBetween(unsigned char* oldPalette, unsigned char* newPalette, int steps);
@@ -51,13 +29,8 @@ void colorPaletteSetTransitionCallback(ColorTransitionCallback* callback);
 void _setSystemPalette(unsigned char* palette);
 unsigned char* _getSystemPalette();
 void _setSystemPaletteEntries(unsigned char* a1, int a2, int a3);
-void _setIntensityTableColor(int a1);
-void _setIntensityTables();
-void _setMixTableColor(int a1);
 bool colorPaletteLoad(const char* path);
 char* _colorError();
-void _buildBlendTable(unsigned char* ptr, unsigned char ch);
-void _rebuildColorBlendTables();
 unsigned char* _getColorBlendTable(int ch);
 void _freeColorBlendTable(int a1);
 void colorPaletteSetMemoryProcs(MallocProc* mallocProc, ReallocProc* reallocProc, FreeProc* freeProc);