diff --git a/EtcLib/Etc/EtcFilter.cpp b/EtcLib/Etc/EtcFilter.cpp
index 298e144..bc899a5 100644
--- a/EtcLib/Etc/EtcFilter.cpp
+++ b/EtcLib/Etc/EtcFilter.cpp
@@ -6,7 +6,7 @@
 namespace Etc
 {
 
-static const double M_PI = 3.14159265358979323846;
+static const double PiConst = 3.14159265358979323846;
 
 inline double sinc(double x) 
 {
@@ -15,7 +15,7 @@ inline double sinc(double x)
         return 1.0;
     }
 
-    return sin(M_PI * x) / (M_PI * x);
+    return sin(PiConst * x) / (PiConst * x);
 }
 
 //inline float sincf( float x )
@@ -296,10 +296,10 @@ int FilterTwoPass( RGBCOLOR *pSrcImage, int srcWidth, int srcHeight,
             }
 
             pPixel = pDestImage + (iRow * destWidth) + iCol;
-            pPixel->rgba[0]   = (unsigned char)(__max( 0, __min( 255.0, dRed)));
-            pPixel->rgba[1] = (unsigned char)(__max( 0, __min( 255.0, dGreen)));
-            pPixel->rgba[2]  = (unsigned char)(__max( 0, __min( 255.0, dBlue)));
-            pPixel->rgba[3] = (unsigned char)(__max( 0, __min( 255.0, dAlpha)));
+            pPixel->rgba[0]   = (unsigned char)(std::max( 0.0, std::min( 255.0, dRed)));
+            pPixel->rgba[1] = (unsigned char)(std::max( 0.0, std::min( 255.0, dGreen)));
+            pPixel->rgba[2]  = (unsigned char)(std::max( 0.0, std::min( 255.0, dBlue)));
+            pPixel->rgba[3] = (unsigned char)(std::max( 0.0, std::min( 255.0, dAlpha)));
         }
     }
 
diff --git a/EtcTool/EtcSourceImage.cpp b/EtcTool/EtcSourceImage.cpp
index 0c64fea..fcb1ac0 100644
--- a/EtcTool/EtcSourceImage.cpp
+++ b/EtcTool/EtcSourceImage.cpp
@@ -97,12 +97,12 @@ namespace Etc
 	{
 		unsigned char* paucPixels = nullptr;
 
-		int iWidth;
-		int iHeight;
-		int iBitsPerPixel;
+		int iWidth = 0;
+		int iHeight = 0;
 		bool bool16BitImage = false;
 	
 #if USE_STB_IMAGE_LOAD
+		int iBitsPerPixel;
 		//if stb_iamge is available, only use it to load files other than png
 		char *fileExt = strrchr(m_pstrFilename, '.');
 
diff --git a/README.md b/README.md
index 632f72a..96678f1 100644
--- a/README.md
+++ b/README.md
@@ -112,7 +112,7 @@ Options:
     -effort <amount>              number between 0 and 100 to specify the encoding quality 
                                   (100 is the highest quality)
     -errormetric <error_metric>   specify the error metric, the options are
-                                  rgba, rec709, numeric and normalxyz
+                                  rgba, rgbx, rec709, numeric and normalxyz
     -format <etc_format>          ETC1, RGB8, SRGB8, RGBA8, SRGB8, RGB8A1,
                                   SRGB8A1 or R11
     -help                         prints this message
@@ -120,6 +120,8 @@ Options:
     -normalizexyz                 normalize RGB to have a length of 1
     -verbose or -v                shows status information during the encoding
                                   process
+	-mipmaps or -m <mip_count>    sets the maximum number of mipaps to generate (default=1)
+	-mipwrap or -w <x|y|xy>       sets the mipmap filter wrap mode (default=clamp)
 
 * -analyze will run an analysis of the encoding and place it in folder 
 "analysis_folder" (e.g. ../analysis/kodim05).  within the analysis_folder, a folder 
@@ -140,10 +142,12 @@ will dictate what error analysis is used in the comparison.
 to apply during the encoding.
 
 * -errormetric selects the fitting algorithm used by the encoder.  "rgba" calculates 
-RMS error using RGB components that are weighted by A.  "rec709" is similar to "rgba", 
-except the RGB components are also weighted according to Rec709.  "numeric" 
-calculates RMS error using unweighted RGBA components.  "normalize" calculates error 
-based on dot product and vector length for RGB and RMS error for A.
+RMS error using RGB components that are weighted by A.  "rgbx" calculates RMS error 
+using RGBA components, where A is treated as an additional data channel, instead of 
+as alpha.  "rec709" is similar to "rgba", except the RGB components are also weighted 
+according to Rec709.  "numeric" calculates RMS error using unweighted RGBA components.  
+"normalize" calculates error based on dot product and vector length for RGB and RMS 
+error for A.
 
 * -help prints out the usage message
 
@@ -154,6 +158,14 @@ based on dot product and vector length for RGB and RMS error for A.
 * -verbose shows information on the current encoding process. It will then display the 
 PSNR and time time it took to encode the image.
 
+* -mipmaps takes an argument that specifies how many mipmaps to generate from the 
+source image.  The mipmaps are generated with a lanczos3 filter using edge clamping.
+If the mipmaps option is not specified no mipmaps are created.
+
+* -mipwrap takes an argument that specifies the mipmap filter wrap mode.  The options 
+are "x", "y" and "xy" which specify wrapping in x only, y only or x and y respectively.
+The default options are clamping in both x and y.
+
 Note: Path names can use slashes or backslashes.  The tool will convert the 
 slashes to the appropriate polarity for the current platform.