diff --git a/libgrit/grit_core.cpp b/libgrit/grit_core.cpp
index 26dfdb9..b110d18 100644
--- a/libgrit/grit_core.cpp
+++ b/libgrit/grit_core.cpp
@@ -149,6 +149,7 @@ void grit_init(GritRec *gr)
 	gr->gfxAlphaColor= clr2rgb(RGB(255, 0, 255));
 	gr->gfxBpp= 8;
 	gr->gfxOffset= 0;
+	gr->gfxIsOffsetOnZero= false;
 	gr->gfxIsShared= false;
 
 	// Map options.
@@ -231,6 +232,7 @@ void grit_copy_options(GritRec *dst, const GritRec *src)
 	dst->gfxAlphaColor= src->gfxAlphaColor;
 	dst->gfxBpp= src->gfxBpp;
 	dst->gfxOffset= src->gfxOffset;
+	dst->gfxIsOffsetOnZero= src->gfxIsOffsetOnZero;
 	dst->gfxIsShared= src->gfxIsShared;
 
 	// Map options.	
diff --git a/libgrit/grit_core.h b/libgrit/grit_core.h
index 0ed237e..1b7ebcb 100644
--- a/libgrit/grit_core.h
+++ b/libgrit/grit_core.h
@@ -272,6 +272,7 @@ struct GritRec
 	bool	 gfxHasAlpha;	//!< Input image has transparent color.
 	RGBQUAD	 gfxAlphaColor;	//!< Transparent color (-gT {num} ). 
 	u32		 gfxOffset;		//!< Pixel value offset (-ga {num}).
+	bool	 gfxIsOffsetOnZero;	//!< Pixel value offset for zero pixel as well. (-gA {num}).
 	bool	 gfxIsShared;	//!< Graphics are shared (-gS).
 		
 // Map:
diff --git a/libgrit/grit_prep.cpp b/libgrit/grit_prep.cpp
index 733efb5..c5812d8 100644
--- a/libgrit/grit_prep.cpp
+++ b/libgrit/grit_prep.cpp
@@ -529,6 +529,7 @@ bool grit_prep_gfx(GritRec *gr)
 {
 	lprintf(LOG_STATUS, "Graphics preparation.\n");		
 
+    int ii;
 	int srcB= dib_get_bpp(gr->_dib);	// should be 8 or 16 by now
 	int srcP= dib_get_pitch(gr->_dib);
 	int srcS= dib_get_size_img(gr->_dib);
@@ -575,14 +576,27 @@ bool grit_prep_gfx(GritRec *gr)
 	//   problems with padding
 	// NOTE: we're already at 8 or 16 bpp here, with 16 bpp already 
 	//   accounted for. Only have to do 8->1,2,4
-	// TODO: offset
+	// TODO: base eBUP big-endian
 	if(srcB == 8 && srcB != dstB)
 	{
 		lprintf(LOG_STATUS, "  Bitpacking: %d -> %d.\n", srcB, dstB);
-		data_bit_pack(dstD, srcD, srcS, srcB, dstB, 0);
+        DWORD base = gr->gfxOffset;
+        if (gr->gfxIsOffsetOnZero)
+            base |= BUP_BASE0;
+		data_bit_pack(dstD, srcD, srcS, srcB, dstB, base);
 	}
-	else
-		memcpy(dstD, srcD, dstS);
+	else {
+        for (ii=0;ii<dstS;ii++) {
+            BYTE bsrcD = srcD[ii];
+            if (bsrcD)
+                dstD[ii] = bsrcD + gr->gfxOffset;
+            else
+                dstD[ii] = 
+                    gr->gfxIsOffsetOnZero
+                    ? bsrcD + gr->gfxOffset
+                    : bsrcD;
+        }
+    }
 
 	//add alpha data for texture formats
 	if((gr->gfxTexMode == GRIT_TEXFMT_A5I3 || gr->gfxTexMode == GRIT_TEXFMT_A3I5))
diff --git a/srcgrit/grit_main.cpp b/srcgrit/grit_main.cpp
index b7c85fc..2b0882c 100644
--- a/srcgrit/grit_main.cpp
+++ b/srcgrit/grit_main.cpp
@@ -81,8 +81,8 @@ const char appHelpText[]=
 "-g | -g!       Include  or exclude gfx data [inc]\n"
 "-gu(8|16|32)   Gfx data type: u8, u16, u32 [u32]\n"
 "-gz[!lhr0]     Gfx compression: off, lz77, huff, RLE, off+header [off]\n"
-//"-ga{n}         Gfx pixel offset (non-zero pixels) [0]\n"
-//"-gA{n}         Gfx pixel offset n (all pixels) [0]\n"
+"-ga{n}         Gfx pixel offset (non-zero pixels) [0]\n"
+"-gA{n}         Gfx pixel offset n (all pixels) [0]\n"
 "-gb | -gt      Gfx format, bitmap or tile [tile]\n"
 "-gB{fmt}       Gfx format / bit depth (1, 2, 4, 8, 16, a5i3, a3i5) [img bpp]\n"
 "-gx            Enable texture operations\n"
@@ -332,7 +332,11 @@ bool grit_parse_gfx(GritRec *gr, const strvec &args)
 			gr->gfxCompression= val;
 
 		// pixel offset
-		gr->gfxOffset= CLI_INT("-ga", 0);
+		gr->gfxOffset= CLI_INT("-gA", 0);
+        gr->gfxIsOffsetOnZero= (bool)gr->gfxOffset;
+        if (!gr->gfxOffset) {
+            gr->gfxOffset= CLI_INT("-ga", 0);
+        }
 	}
 	else
 		//# PONDER: can img really be excluded from processing?