return tex2D(inputTex, Uv.xy * float2(4.0, 4.0));

float4 DownsamplePS( float2 Tex : TEXCOORD0 ) : COLOR0 
{
   // start with an empty color
   float4 color = float4(0.0f, 0.0f, 0.0f, 0.0f); 
       
   // accumulate value off all colors in 4x4 square
   color += tex2D( orgRT, Tex + float2( 0.0 , 0.0 )); // get (0,0) color
   color += tex2D( orgRT, Tex + float2( 1.0 , 0.0 )); // add (1,0)'s color to it
   color += tex2D( orgRT, Tex + float2( 2.0 , 0.0 )); // add (2,0)'s color to it
   color += tex2D( orgRT, Tex + float2( 3.0 , 0.0 )); // add (3,0)'s color to it
   color += tex2D( orgRT, Tex + float2( 0.0 , 1.0 )); // add (0,1)'s color to it
   color += tex2D( orgRT, Tex + float2( 1.0 , 1.0 )); // add (1,1)'s color to it
   color += tex2D( orgRT, Tex + float2( 2.0 , 1.0 )); // add (2,1)'s color to it
   color += tex2D( orgRT, Tex + float2( 3.0 , 1.0 )); // add (3,1)'s color to it
   color += tex2D( orgRT, Tex + float2( 0.0 , 2.0 )); // add (0,2)'s color to it
   color += tex2D( orgRT, Tex + float2( 3.0 , 2.0 )); // add (1,2)'s color to it
   color += tex2D( orgRT, Tex + float2( 2.0 , 2.0 )); // add (2,2)'s color to it
   color += tex2D( orgRT, Tex + float2( 3.0 , 2.0 )); // add (3,2)'s color to it
   color += tex2D( orgRT, Tex + float2( 0.0 , 3.0 )); // add (0,3)'s color to it
   color += tex2D( orgRT, Tex + float2( 1.0 , 3.0 )); // add (1,3)'s color to it
   color += tex2D( orgRT, Tex + float2( 2.0 , 3.0 )); // add (2,3)'s color to it
   color += tex2D( orgRT, Tex + float2( 3.0 , 3.0 )); // add (3,3)'s color to it
 
   // Adjust the accumulated amount by lum factor
   float lum = dot(color, luminance_factor); 

   // get average of the 16 samples
   lum *= 0.0625;

   return lum;
}

float4 GreyScaleDownSample( float2 UV : TEXCOORD0 ) : COLOR0{  float offset1 = 1/1280; // create normalized coordinate offsets from input texture   float offset2 = 1/720;  float4 color = 0.0f;  float3 weight = float3( 0.299f, 0.587f, 0.114f );  UV.xy = UV * float2(2.0, 2.0); // offset each read times 2 in xy to halve the output  color += tex2D( sourceRT, UV);                                // get the color of the target texel   color += tex2D( sourceRT, UV + float2( -offset1, 0.0f ));     // add the color of the texel to the left  color += tex2D( sourceRT, UV + float2( -offset1, -offset2 )); // add the color of the texel to the left and above  color += tex2D( sourceRT, UV + float2(  0.0f   , -offset2 )); // add the color of the texel to the above  // Adjust the accumulated amount by lum weight  float lum = dot(color, weight);   // get average of the 4 samples  lum *= 0.25;  return lum;}

float4 DownSample( float2 UV : TEXCOORD0 ) : COLOR0{  float TexelSize = 1/256; // for a 256x256 source image  float3 vSample = 0.0f;  UV.xy = UV * float2(4.0f, 4.0f); // offset each read x4 to scale down output image to 1/4 size  // add column 0 colors  vSample += tex2D( sourceRT, UV + float2( 0.0f * TexelSize, 0.0f * TexelSize )); // get the color of the texel row 0 column 0  vSample += tex2D( sourceRT, UV + float2( 1.0f * TexelSize, 0.0f * TexelSize )); // add the color of the texel row 1 column 0   vSample += tex2D( sourceRT, UV + float2( 2.0f * TexelSize, 0.0f * TexelSize )); // add the color of the texel row 2 column 0  vSample += tex2D( sourceRT, UV + float2( 3.0f * TexelSize, 0.0f * TexelSize )); // add the color of the texel row 3 column 0  // add column 1 colors  vSample += tex2D( sourceRT, UV + float2( 0.0f * TexelSize, 1.0f * TexelSize )); // add the color of the texel row 0 column 1  vSample += tex2D( sourceRT, UV + float2( 1.0f * TexelSize, 1.0f * TexelSize )); // add the color of the texel row 1 column 1  vSample += tex2D( sourceRT, UV + float2( 2.0f * TexelSize, 1.0f * TexelSize )); // add the color of the texel row 2 column 1  vSample += tex2D( sourceRT, UV + float2( 3.0f * TexelSize, 1.0f * TexelSize )); // add the color of the texel row 3 column 1  // add column 2 colors  vSample += tex2D( sourceRT, UV + float2( 0.0f * TexelSize, 2.0f * TexelSize )); // add the color of the texel row 0 column 2  vSample += tex2D( sourceRT, UV + float2( 1.0f * TexelSize, 2.0f * TexelSize )); // add the color of the texel row 1 column 2  vSample += tex2D( sourceRT, UV + float2( 2.0f * TexelSize, 2.0f * TexelSize )); // add the color of the texel row 2 column 2  vSample += tex2D( sourceRT, UV + float2( 3.0f * TexelSize, 2.0f * TexelSize )); // add the color of the texel row 3 column 2  // add column 3 colors  vSample += tex2D( sourceRT, UV + float2( 0.0f * TexelSize, 3.0f * TexelSize )); // add the color of the texel row 0 column 3  vSample += tex2D( sourceRT, UV + float2( 1.0f * TexelSize, 3.0f * TexelSize )); // add the color of the texel row 1 column 3  vSample += tex2D( sourceRT, UV + float2( 2.0f * TexelSize, 3.0f * TexelSize )); // add the color of the texel row 2 column 3  vSample += tex2D( sourceRT, UV + float2( 3.0f * TexelSize, 3.0f * TexelSize )); // add the color of the texel row 3 column 3  vSample *= 0.0625f;  // divide by 16 to get the average of the 16 samples  return float4(vSample, 1.0f); }