Silverlight Image Panning - silverlight

Question

I am working on silverlight application and I had use the pixel shadder with brightness and contrast which is working fine. so I had tried with panning center x,y but it will not working so how I can add this panning.
My PS file like this.
/// <class>briconEffect</class>
/// <description>An effect that controls brightness and contrast.</description>
//-----------------------------------------------------------------------------------------
// Shader constant register mappings (scalars - float, double, Point, Color, Point3D, etc.)
//-----------------------------------------------------------------------------------------
/// <summary>The brightness offset.</summary>
/// <minValue>-1</minValue>
/// <maxValue>1</maxValue>
/// <defaultValue>0</defaultValue>
float Brightness : register(C0);
/// <summary>The contrast multiplier.</summary>
/// <minValue>0</minValue>
/// <maxValue>2</maxValue>
/// <defaultValue>1.5</defaultValue>
float Contrast : register(C1);
/// <summary>The gamma correction exponent.</summary>
/// <minValue>0.5</minValue>
/// <maxValue>2</maxValue>
/// <defaultValue>0.8</defaultValue>
float Gamma : register(C2);
/// <summary>Change the ratio between the Red channel</summary>
/// <minValue>0/minValue>
/// <maxValue>1</maxValue>
/// <defaultValue>0.5</defaultValue>
float RedRatio : register(C3);
/// <summary>Change the ratio between the Blue channel </summary>
/// <minValue>0/minValue>
/// <maxValue>1</maxValue>
/// <defaultValue>0.5</defaultValue>
float BlueRatio : register(C4);
/// <summary>Change the ratio between the Green channel</summary>
/// <minValue>0/minValue>
/// <maxValue>1</maxValue>
/// <defaultValue>0.5</defaultValue>
float GreenRatio : register(C5);
//--------------------------------------------------------------------------------------
// Sampler Inputs (Brushes, including Texture1)
//--------------------------------------------------------------------------------------
sampler2D Texture1Sampler : register(S0);
//--------------------------------------------------------------------------------------
// Pixel Shader
//--------------------------------------------------------------------------------------
float4 main(float2 uv : TEXCOORD) : COLOR
{
float4 pixelColor = tex2D(Texture1Sampler, uv);
pixelColor.rgb = pow(pixelColor.rgb, Gamma);
pixelColor.rgb /= pixelColor.a;
// Apply contrast.
pixelColor.rgb = ((pixelColor.rgb - 0.5f) * max(Contrast, 0)) + 0.5f;
// Apply brightness.
pixelColor.rgb += Brightness;
// Return final pixel color.
pixelColor.rgb *= pixelColor.a;
pixelColor.r = pixelColor.r * (1-RedRatio ) ;
pixelColor.b = pixelColor.b * (1-BlueRatio ) ;
pixelColor.g = pixelColor.g * (1-GreenRatio ) ;
return pixelColor;
}