diff --git a/reactos/sdk/include/psdk/gdipluscolormatrix.h b/reactos/sdk/include/psdk/gdipluscolormatrix.h
index fbf1b2a402f..44016ff3451 100644
--- a/reactos/sdk/include/psdk/gdipluscolormatrix.h
+++ b/reactos/sdk/include/psdk/gdipluscolormatrix.h
@@ -48,10 +48,23 @@ struct ColorMap
     Color newColor;
 };
 
+enum HistogramFormat
+{
+    HistogramFormatARGB,
+    HistogramFormatPARGB,
+    HistogramFormatRGB,
+    HistogramFormatGray,
+    HistogramFormatB,
+    HistogramFormatG,
+    HistogramFormatR,
+    HistogramFormatA,
+};
+
 #ifndef __cplusplus
 
 typedef enum ColorAdjustType ColorAdjustType;
 typedef enum ColorMatrixFlags ColorMatrixFlags;
+typedef enum HistogramFormat HistogramFormat;
 typedef struct ColorMatrix ColorMatrix;
 typedef struct ColorMap ColorMap;
 
diff --git a/reactos/sdk/include/psdk/gdiplusenums.h b/reactos/sdk/include/psdk/gdiplusenums.h
index e30c3e74560..477caab4663 100644
--- a/reactos/sdk/include/psdk/gdiplusenums.h
+++ b/reactos/sdk/include/psdk/gdiplusenums.h
@@ -47,7 +47,7 @@ enum DriverStringOptions
    DriverStringOptionsCmapLookup      = 1,
    DriverStringOptionsVertical        = 2,
    DriverStringOptionsRealizedAdvance = 4,
-   DriverStringOptionsLimitSubpixel   = 4
+   DriverStringOptionsLimitSubpixel   = 8
 };
 
 enum FillMode
diff --git a/reactos/sdk/include/psdk/gdiplusflat.h b/reactos/sdk/include/psdk/gdiplusflat.h
index c6f16c4bf4c..0d6d9eaae3f 100644
--- a/reactos/sdk/include/psdk/gdiplusflat.h
+++ b/reactos/sdk/include/psdk/gdiplusflat.h
@@ -41,6 +41,8 @@ GpStatus WINGDIPAPI GdipSetAdjustableArrowCapWidth(GpAdjustableArrowCap*,REAL);
 /* Bitmap */
 GpStatus WINGDIPAPI GdipBitmapApplyEffect(GpBitmap*,CGpEffect*,RECT*,BOOL,VOID**,INT*);
 GpStatus WINGDIPAPI GdipBitmapCreateApplyEffect(GpBitmap**,INT,CGpEffect*,RECT*,RECT*,GpBitmap**,BOOL,VOID**,INT*);
+GpStatus WINGDIPAPI GdipBitmapGetHistogram(GpBitmap*,HistogramFormat,UINT,UINT*,UINT*,UINT*,UINT*);
+GpStatus WINGDIPAPI GdipBitmapGetHistogramSize(HistogramFormat,UINT*);
 GpStatus WINGDIPAPI GdipBitmapGetPixel(GpBitmap*,INT,INT,ARGB*);
 GpStatus WINGDIPAPI GdipBitmapLockBits(GpBitmap*,GDIPCONST GpRect*,UINT,
     PixelFormat,BitmapData*);
@@ -262,6 +264,7 @@ GpStatus WINGDIPAPI GdipGetWorldTransform(GpGraphics*,GpMatrix*);
 GpStatus WINGDIPAPI GdipGraphicsClear(GpGraphics*,ARGB);
 GpStatus WINGDIPAPI GdipGetVisibleClipBounds(GpGraphics*,GpRectF*);
 GpStatus WINGDIPAPI GdipGetVisibleClipBoundsI(GpGraphics*,GpRect*);
+GpStatus WINGDIPAPI GdipInitializePalette(ColorPalette*,PaletteType,INT,BOOL,GpBitmap*);
 GpStatus WINGDIPAPI GdipIsClipEmpty(GpGraphics*, BOOL*);
 GpStatus WINGDIPAPI GdipIsVisiblePoint(GpGraphics*,REAL,REAL,BOOL*);
 GpStatus WINGDIPAPI GdipIsVisiblePointI(GpGraphics*,INT,INT,BOOL*);